The Hi Power clones are a little complicated to describe.
The FEG Hi Powers:
The FEG P9 was a near perfect Pre-Mk II Hi Power clone and it has 100% parts interchangeability with the Browning Hi Power.
The First Generation P9M is for all intents and practical purposes a Pre-Mk II Hi Power clone, but with a revised slide stop design and larger three dot sights. That's what got it the "M" for "Modositott" which just means "Modified". With the exception of the slide release and the matching slide release cut in the slide it also has 100% parts interchangeability with the Browning Hi Power. You can however modify the larger Browning Mk III slide stops to fit if you desire.
The Second Generation P9M shares the same "P9M" model number but it's not a true Hi Power. This variant uses the S&W style barrel and locking system.
The only way to tell it apart from the earlier FEG P9 and 1st Gen P9M is the absence of the oval shaped "footprint" on the right side of the frame that is caused by the cross both being polished flush with the frame. If you can't see the foot print, it's a 2nd Gen P9M and parts commonality with a Browning Hi Power is very low - around 20%.
It's even more confusing as KBI imported all three of the above pistols as "PJK-9HP" pistols, so the KBI model number is totally meaningless.
KBI also imported the FEG FP9, which is a ventilated rib version of the 1st Gen P9M. As far as I know none of them were made with the S&W barrel system, but that's not a guarantee - you'll want to look for the footprint.
KBI also imported parts directly from FEG to manufacture the Charles Daly Hi Power (Charles Daly was their high end banner) and they are very nicely made Hi Powers. They are Pre-Mk II Hi Power clones with the exception of an extended slide release and a slide milled for Novak sights. They were assembled in the US, first By Dan Wesson and later by Magnum Research, and thus avoided import stamps. The Dan Wesson assembled guns have the slide milled for Ho Power style Novak sights, while the Magnum Research assembled pistols have the side milled for the 1911 style Novak sight.
TGI didn't help the situation either as they also imported 1st and 2nd Gen P9Ms and both models just had the FEG model number, so they are both marked "P9M". Once again, you'll need to look for the foot print to confirm it's a Hi Power clone and not a S&W / Hi Power hybrid.
There are also double action 9mm Para FEG pistols are basically a clone of the S&W Model 59 and the only resemblance to a Hi Power is in the shape of the muzzle end of the slide. Other than that they look a good bit like a S&W. The FEG P9R is the most common double action FEG pistol variant and many people confuse the model number with the P9M, and thus refer to them as "FEG Hi Powers", when they are not.
FEG also made some P9 Hi Powers for Israel and per the customer's request marked them as FN Browning made pistols. I'm not sure why it mattered to the Israelis but the end result was an unlicensed use of the trademark and a lawsuit.
The Argentine Hi Powers:
They come in three flavors.
Argentina bought FN Hi Powers in 1960 and liked them enough that they negotiated an agreement to make them under license to FN, under the supervision of FN inspectors, and on FN tooling. They did this from 1969-1989. These Argentine Hi Powers are a clone of the 1965 model Mk I Hi Power, but with a Phosphate finish. They obviously share 100% parts interchangeability with their FN made cousins. These were made primarily for the Argentine military and police forces by Direccion General Fabrications Militaries (commonly called FM) at their arms factory, Fabrica Armas Portatiles Domingo F. Matheu in Rosario, and they were not exported as new firearms - which I suspect was a condition of the license agreement.
However, in 1990, FM began producing an unlicensed version of the Hi Power for civilian export sales and added many of the Mk II Hi Power improvements, like the straight feed ramp. They called it the "M90", based on the year they started production. They are mostly a Mk II Hi Power, but are not made under FN inspection or supervision, and there are some differences such as a 1911-style slide cut near the muzzle, the deletion of the lanyard ring, and the use of plastic grips.
There is also a later (1995) FM 95 that has an ambidextrous safety and a firing pin safety like the Mk III Hi Power as well as the three bar sights and dove tailed front sight like the MK III Hi Power.
In general the quality on these later FM 90 and FM 95 Hi Power clones isn't considered to be up to FN standards, which isn't surprising given that they sold for half the cost of an FN Hi Power.
Functionally speaking, The major fault with these pistols is the magazines, which tend to be poor quality, but factory Hi Power magazines fit perfectly and work great in them.
Humped versus straight feed ramps:
Generally speaking the Mk I HI Powers and their FEG and FM clones have a humped feed ramp that was optimized for ball ammo.
Reports are mixed on the FM 90s and FM 95s as many of them seem to also have the earlier humped feed ramp, so it may have been a case of FM using whatever they had on hand, and or being very slow in transitioning to the Mk II stye barrel.
Opinions vary on how well the humped feed ramps feed hollow points. I've had great luck with hollow points in my FEG 1st Gen P9M, but I primarily use 124-125 grain hollow points, and in particular the 125 gr Hornady XTP and the Remington 124 gr Golden Saber.
Personally I think the problem is over blown as hollow points have improved over the years as have magazines. I use both the stock FN/Browning magazines as well as MecGar magazines - and MecGar is the OEM for the FN/Browning magazines, so aside from the mouse trap feature on the Fn magazines, they are the same magazine made on the same tooling. Stay away from all the other third party magazines and you should be fine - but YMMV.
If you have issues, it's not difficult for a gunsmith to straighten the feed ramp.
My Hi Powers:
I have both Mk III and Mk III SFS Hi Powers as well as an FEG 1st Gen P9M that I converted to SFS configuration using the FN Browning parts that are sold by Cylinder and Slide.
The SFS conversion eliminates the hammer bite that can be caused by the round hammer on some Hi Powers (the FEGs come with both round and spur hammers, apparently based on the mood that day in the factory as there isn't any pattern to it based on SN).
It modifies the operating system so that the safety is applied when the hammer is pressed forward from it's cocked position. This leaves the hammer spring cocked and locks the sear, but moves the upper portion of the hammer forward down onto a hammer block. It's in Condition 1, but the hammer doesn't make it appear that way. To fire, you just move the safety level down, and the hammer pops back into position. Compare the hammer position in the top picture (cocked and locked) with the slightly lower hammer and safety positions in the bottom picture (hammer down, safety off).
The SFS system also provides for an ambidextrous safety not otherwise found on the Mk I Hi Powers.
Like any safety replacement it's not a 100% drop in conversion as some hand fitting is required, which is the norm on a Hi Power safety swap. In other words, the parts commonality between my FEG and my FN SFS parts was within the ball park for Hi Power safety parts.
The exception of course was the slide lever that came with the SFS kit. It took a little re-profiling to fit the smaller slide cut on the FEG:
Comparing the BHP to the FEG P9M:
I have found both of them to be very reliable pistols, but in dirty field conditions, I'd prefer to carry the FEG. The tolerances are a little looser and the chamber is a just a bit larger. That follows the same pattern and design preferences I've seen comparing the Walther PP and PPK/S with the FEG AP and APK clones of those pistols. The pay off is superb reliability, but at the cost of some accuracy.
Still, the FEG is capable of fine combat accuracy and unless you're planning on using the pistol for centerfire class bullseye competition, an FEG should serve you as well as an FN Hi Power.
My Mk III SFS Hi Power has a very disable painted finish, that has held up extremely well, but it's not what people associate with the finish on older Hi Powers.
My FEG 1st Gen P9M has a very nicely polished and blued finish that is apparently found primarily on the early P9Ms as the later ones seem to have a matte finish.