My USP-45F is my "go-to" gun of choice. Quality is top notch as is accuracy and reliability. The recoil reduction system works great where 230 grain ammo feels like 185 grain ammo through lesser designs. Some folks complain about the propriety rail design rather than the standard picatinny rail that is so common now. Keep in mind H&K pioneered the rail design with the Mk23 and USP designs before there was such a thing as a rail on a pistol. These were the first and with no standard to go by, I won't fault them for it. Besides, if it really is an issue, there are adaptors that will mate up with the USP rail to work with standard lights and lazers. Others complain about the poor trigger is solved by either going with the match trigger like I did on my USP-45F or the LEM trigger like I did on my USP-40C.
One other thing about the USP is the ability to be carried cocked and locked yet still have a second strike capability or the option to carry it hammer down like a traditional DA/SA pistol. Another advantage to the USP that every other maker out there lacks the foresight of is operations in cold weather. Now when I talk about cold weather, I'm NOT talking about spending an hour or two out in 20-30 degree temps. I'm talking about spending entire days in 20-30 BELOW zero temps! True, I have Glocks, Sigs, 1911s, CZs and others that work just fine in cold weather as well but ever try to get a glove that's heavy enough to keep your fingers from freezing and falling off in those conditions in the trigger guard or say a Glock, Sig or 1911? Probably not going to happen and if it does, it's a tight fit that is now on the brink of accidently depressing the trigger because you don't have enough room. Not a problem with a cocked and locked USP since the trigger guard is freakin' huge! The CZ-75 and EAA Witness come close but still not as large as the USP design. You may think this is a minor thing but if you spend any amount of time in those conditions, it becomes pretty danged important!
Another thing about the USP is you can make it any way you want it. Right handed and want to carry it cocked and locked only, there's a variant for that. DAO or lefty that wants a decocking lever only? There's a variant for that. Maybe you're like me and like the safety lever and decocking feature but want it in ambidextrious design. Yup, there's a variant for that one too. Maybe you want the precocked mainspring and light pull of the LEM trigger. That's do-able and maybe you want that same LEM trigger but with a manual safety because you are concerned about gun-snatching bad guys. Yup, you can even do that too! Standard barrels, threaded barrels, barrels with O-rings for enhanced accuracy can be had as well as various sights can be had as well. No, it's not anywhere close to the 1911 or Glock for aftermarket parts but then again, it really doesn't need any either. So, does this answer your question is the USP is really that good?