I've had both (none now). Seriously was not really impressed with either (after the initial euphoria had died down). I'd give the HK45 (not the USP) an edge on the grip, with the FNP45 the edge on mag capacity. Other than that, blah.
Last year I had an itch for some .45 shopping. I was getting close to buying the FN, I tried out the HK and also the M&P. :yawn:
I could not make up my mind so I thought of getting another G21 but grabed an STI :supergrin: instead
I have 2 FNP-45USGs and 2 HKUSP45s one of which is a 6"Elite. The HKs will feed everything. The FNs are great hardball guns but are a little finicky feeding +P and certain wide nosed hollowpoints from my experience. Others on the FNForum report having no issues. For hardball only I like the FN for its 15+1 capacity. Both guns operate the same which is why I like them. Really like the 1911 style safety which allows Condition 1 carry if you so choose, or decocked with safety either on or off. The FN controls are completely ambidextrious. FNP is several hundred dollars less expensive if that matters. If the FN fed everything to my level of expectations it would be my top choice.
FNP-45 (non-USG) owner here. Good gun for the money, although I have had some feeding issues with mine. Some slightly out of spec. WWB caused improper stacking of the rounds in the magazine.
IMO, the magazines are the weak link. FN needs to add some anti-tilt legs onto the followers.
Otherwise the gun is very accurate and soft recoiling. Trigger is decent in both SA and DA. The downside is not alot of people make holsters/sights for them and the gun is very large, not really good for CCW.
I am a little biased because I carry an HK45 on duty. Real night sights are available for them now as well as more holster options. My HK has been 100% after roughly 3-4k rounds. There is a thread on HK Pro where one guy was up to 15k rounds on the HK45 with zero malfunctions or parts breakage.
The FN is a fine gun too, but the mag capacity makes it HUGE. I don't own one, so I am not sure about availability of holsters and other accesories.
Bottom line is that they are both good guns, but for me the HK has the edge.
My FNP-45 USG had loads of failure to feed issues with various hollow-point cartridges (Gold Dot and HSTs). It took two trips back to the FNH factory and was ultimately replaced with a new pistol by FNH. I do not consider the design to be reliable enough for serious consideration.
I have a Glock 21 which has functioned perfectly with every single type of round I've placed in it, has less perceived recoil despite a lower weight, sacrifices only one round in the magazine when comparing flush fitting magazines (the 15 round FNP-45 magazine has an extended floor plate), and it costs less to boot. I had considered the HK45 but I couldn't figure out any reason why it cost nearly $1,000 and only held 10 rounds. The double action trigger is among the worst in its class IMO.
I know a lot of people will disagree with this, but IMO HKs feel cheap. Although the HK 45 is a significant step up from the USP IMO when it comes to this. I would actually take the HK 45, but by a small margin and I really wish it had a better trigger. I really don't think HKs are worth the extra cash and should be closer to 6 or 7 hundred for their most expensive models.
I like what FN has done with there 45acp, but I use to own an HK45 and I really liked it and there was no issue at all, I got rid of it because of the size and got a HK45C instead and I have to admit its been my favorite gun since.....