I had a .45F for a few years. I'm not much on the .40, but the .45 was a real tack driver. Very rugged and boringly reliable. There were only 2 drawbacks for me. One, that thing was huge. It wasn't the easiest to conceal (if that matters to you). The .40C would be smaller, but the USP compacts are usually about the size of most fullsize guns. Two, the grip angle was wrong for me. I either needed to go w/just the USP or keep my other guns, and I wasn't about to give up my CZ.
I guess there is one other thing, the rails on the USP are only used on the USP, so you can't get any light you want w/out an adapter. Don't know if that matters to you, but it's something to think about.