Which is best: CZ-75 or Browning Hi Power? This is a widely discussed topic on gun boards in recent years and one I'm frequently asked. There is not a simple answer, but I will submit my observations.
If you are not comfortable with cocked-and-locked carry for defensive purposes, I'd go with the CZ. Though long, the double-action first shot is usually pretty smooth and exceptionally so in some examples of the gun. Trigger reach is long, too long for some. I find it usable, but any longer and I could not. (It's not really an issue with me as I carry cocked-and-locked.) If you are confident with Condition One carry and have smaller hands, go with the Hi Power. If either works for you in this mode, go with the one that feels best to you. The thumb safety on the CZ is normally more "positive" in that it clicks into both "on" and "off" positions. Hi Powers do not. I personally prefer the more positive feeling thumb safety on the CZ, but have not had any problems safety-wise with the Hi Power in over thirty-years of carrying. This assumes a good holster. I do not recommend the Hi Power for just sticking in the waistband without a holster. If you carry that way I believe the CZ to be the more prudent choice; carried cocked and locked you have a more positive thumb safety engagement OR you could opt to carry in the double-action mode under such circumstances. The Hi Power thumb safety can be made to have more positive engagement by the use of a Cylinder & Slide safety or by having a gunsmith work on the existing one and the detents in the frame that the safety engages. Out of the box, I believe that the CZ has the better thumb safety.
Fixed sights on the Mk III Hi Power and the CZ75B are equivalent in my opinion. Both offer sight pictures I find very acceptable for both range use as well as for serious concerns. This is subjective and others might not agree. If this is the case, popular sights such as those from Novak can be installed on either pistol. I do not find the sights a determining factor for or against either the current Hi Powers or CZ's. I think you will find more gunsmiths familiar with adding aftermarket sights to the Hi Power than the CZ, but either can receive this modification. If you are comparing a Pre-B CZ-75 to a Mk III Hi Power or its variants, the Hi Power has sights that are easier to see. Conversely a classic Hi Power (Pre-Mk II) having fixed sights does not offer the sight picture of the CZ-75B. I consider the small fixed sights offered on the Pre-B CZ and the classic Hi Power equivalent…and lacking for shooting at speed or under dim light.
Here is a CZ75 compared to a Browning Hi Power. The Hi Power is a bit more compact.
The CZ-75B is slightly larger than the Hi Power. Pictures do not really show this difference as much as when they're handled side by side in my experience. The butt on the full-size CZ is longer than that of the Hi Power. Of course the CZ pistols can be had in compact versions. Right now the FN-manufactured Hi Power is found only in standard size. FM offers a compact slide/bbl arrangement called the "Detective" model and some custom 'smiths offer a cut down version of the Hi Power, but it is expensive. The CZ is slightly heavier than the Hi Power, but differences that are actually felt are for all practical purposes negligible.
The Hi Power (top) is slightly thinner than the CZ 75. Both of these pistols have been fitted with Novak Low Mount fixed sights.
From the bottom careful examination will show that the CZ75 butt is longer than the Hi Power. In this example, it is thicker as well. Grips exist for the CZ that make such differences negligible. The Hi Power shown has thin Spegel delrin grips while the CZ has factory wood grips.
Out of the box the CZ will usually have a lighter single-action trigger pull than the Hi Power, but the Hi Power will normally have a crisper break. Due to the function of the CZ when the trigger is pressed for a single-action shot, the hammer is cammed back very slightly before it is released to strike the firing pin. The Hi Power trigger pull can be cleaned up and lightened by many gunsmiths if necessary. Likewise, the trigger pull on the CZ can be smoothed if desired, but the camming will have to remain; it's just built in and part of the package. This does represent a sear/hammer setup less prone to hammer follow (hammer not staying cocked and falling to the half-cock position) after the pistol's been shot more than a little.
Here you can see the sear and the hammer's sear hooks. The angle on them is such that as the sear is raised by the trigger pull, the hammer moves rearward a fraction of an inch.
The Hi Power has the magazine disconnect sometimes called a magazine "safety." The CZ does not. It's easily removed from the Hi Power, but some are hesitant to do so for fear of possible civil litigation in the event of a shooting. If you cannot abide the magazine disconnect but don't want to remove it, the CZ is the choice between the two guns.
Both pistols are currently made with quality cast frames. For those insisting on forged frames only, Hi Powers made before about '93 can still be had with forged. Personally, I think the current cast frame Hi Powers are very, very usable and more capable of handling hotter loads than the older guns, but either can serve well when +P ammunition is properly sprung. Mike Eagleshield of CZ-USA reports that the CZ's hold up to lots of shooting but does recommend the use of a bit heavier recoil spring than the factory standard 14-lb if using warm loads. He does not report any frame or slide failures, but has mentioned that slide stops on the CZ's have broken when hot loads are regularly used with the 14-lb. spring. I have 18.5-lb recoil springs and they work fine with both standard and +P ammunition, but this is nearly too much. I think that probably a 16 or 17-lb recoil spring in the CZ is a better choice if the shooter is going to be shooting both types of ammunition and plenty if using primarily standard pressure ammo. In the Hi Power I also use 18.5-lb. recoil springs. This is a bit heavier than the factory 17-lb. recoil spring, and I've experienced no problems with standard or hot ammo.
I routinely use shock buffers from Buffer Technology in both guns. Some consider these as unnecessary, but I definitely think they reduce pounding between the slide and frame. If you have concerns over reliability, there's nothing to say that they cannot be used for range work exclusively. They can be removed if the gun's being used for protection at home or when carried.
The Hi Power tends to bite more shooters' hands than the CZ, particularly the B version having the ring hammer. Hi Power tangs are short, and folks with fleshy hands are frequently nipped or pinched by this pistol's hammer. The CZ tang is generous, and its ring hammer is much more abbreviated than the FN factory ring hammer. Hi Powers having spur hammers can be easily altered to avoid hammer bite or replaced with the Cylinder & Slide Type I ring hammer. With the older CZ75's, I experienced hammer bite from their spur-type hammers and have shortened the spurs on them, which eliminated the problem. This is rarely a problem on the CZ75B.
Both pistols are very accurate for service handguns. Neither is built as a match shooter's target pistol, but both are capable of under 3" groups at 25 yards with ammo the gun favors. Both will shoot in the 3" area with most factory loads. Either pistol is capable of delivering better groups than most shooters. Both have twists of approximately 1:10. I have not noticed either maker's barrel wearing out more quickly than the other. For shooters wanting fitted match barrels, Barsto offers stainless steel barrels for either gun.
The CZ75 is capable of satisfactory accuracy for most shooters' needs. This group was fired with the popular Winchester USA 115-gr. FMJ. The fixed sights on this Pre-B are not nearly so visible as those on the B versions or current production Hi Powers. I find these OK for slow-fire, but lacking at speed.
The Mk III Hi Power is capable of more than enough intrinsic accuracy for most real world needs. I wouldn't make my decision on which pistol is best based strictly on mechanical accuracy. Both are quite capable.
Since the Mk II Hi Power hit the scene in the early '80's, the Hi Power's feed ramp has been changed for more reliable feeding of ammunition other than FMJ. The "hump" was removed, and I've found the Hi Power to feed just about any commercially produced JHP. Ditto the CZ pistols. Current pistols from either maker have a feed ramp most conducive to reliable feeding.
Current Mk III's, Standards, or Practicals come with internal firing pin safeties. So does the CZ75B. In fact this is one distinction between the CZ75 and the B version. The system on the Hi Power required changing the shape of the sear lever, machining an opening into the firing pin track and adding one spring at the forward end of the lever. The CZ system is more akin to the Series 80s Colt. With the Hi Power the firing pin remains in place with the traditional retaining plate, as did the Pre-B CZ. The CZ75B retains the firing pin via a horizontal roll pin in the slide. (If you dry-fire the CZ75B, I suggest using a dummy round or snap cap. Without it the forward movement of the firing pin is stopped when a notch in it hits the roll pin. Eventually this can damage either the firing pin or the roll pin.) The Hi Power's firing pin is more easily removed for cleaning, replacement, etc.
The Hi Power internal firing pin block doesn't seem to affect trigger pull as can the CZ75B's system. In my CZ75B, the single-action pull was marred with extreme grittiness right at the break due to the firing pin block being rough and rubbing when pushed upward to free the firing pin. Other examples did not or were much less noticeable. Of course the Hi Power's magazine disconnect can make its trigger pull quite gritty. Either can be corrected via a gunsmith.
While most of us understand that the proper way to chamber a round in the Hi Power or CZ is from the magazine, some do still drop a round in the chamber and let the slide slam shut. I've seen a couple of CZ's break extractors doing this. I have not seen this on the Hi Power.
Both guns eject positively, and I've experienced no problems with either assuming proper cleaning and maintenance. Either of these pistols is very reliable in most instances, and I've seen this long term. I trust either for defensive use.
Original-capacity magazines are more available for the 13 shot 9mm Hi Power than the 15 shot 9mm CZ, and aftermarket magazines exist for both. Some of these non-original magazines will not fit the Pre-B CZ's. More seem to fit the Hi Powers, but some of the shoddier ones will hang. Factory magazines limited to 10 rounds have worked fine for me in the Hi Power, but I only own two. I've heard some reliability complaints concerning 10 round magazines from CZ; these have abated, so perhaps that was limited to a bad run of them. I have noticed with some CZ 15 shot magazines that the magazine spring seems a bit light. Some would not reliably feed +P JHP's. This was easily corrected by using Wolff +5% increased-strength magazine springs. The +10% springs worked fine as well. It may not be a problem with your CZ, but always test the individual pistol for reliability with "serious" ammunition.
The Hi Power magazine disconnect often prevents magazines from falling free of the pistol when the release is pressed. Likewise, the CZ pistols have a bowed flat spring called the magazine brake to prevent free-falling magazines. Removing the disconnect eliminates it on the Hi Power. Similarly the brake can be very easily removed from the CZ and then replaced for the same thing. Do not simply remove the brake. If this is done, the rear of the magazine can hit the frame near the grip screw holes and be damaged during an energetic magazine change. CZ also offers a flat spring to replace the bowed one if one prefers that route. I simply removed the bows in mine and replaced them.
Contrary to what's sometimes said, the CZ is not based on the Hi Power. They may be somewhat similar in appearance, but their internals differ very significantly. The CZ is considerably more complex and difficult to detail strip. If being able to completely disassemble a pistol for cleaning, inspection, or repair is important to you, the Hi Power is probably the better choice.
The CZ will not command as much should you opt to trade it for another firearm or sell it. On the other hand, they cost less NIB than an FN or Browning-marked Hi Power. I think they're exceptional buys and rate them as equivalent in overall quality. I do not care for the plastic guide rods in current CZ pistols, but they seem to work fine. CZ is not as well known here among many, as is "Browning." (FN makes all Browning Hi Powers. Browning Arms Co imports them, but FN manufactures them.)
There are more aftermarket sights, safeties, grips, etc. for the Hi Power than the CZ if this is a consideration. Factory parts for the CZ are not as expensive as those for the Browning Hi Power, and I have found CZ USA to be very good to their customers with regard to support and assistance.
Between the two guns, I prefer the Hi Power. At the same time I have no intention of getting rid of my CZ75 9mm's. If I could not have a Hi Power, the CZ would easily be my second choice for an all around 9mm pistol.