I have the P2000 as an issued weapon. I really, really hate it. It is super finiky with ammo even when spotless. The LEM trigger is a joke at best, the slide stop sometimes catches on my strong hand tumb and prevents slide lock, and the magazine release is absolutely absurd. Please don't further this insanity by purchasing this pos.
The USP full sized isn't great, but better, the .40cal compact is pretty much the same deal. POS.
The P30 has a pretty good feel man. If you are insistent on going with one of the HKs for ccw that is probably your best bet. Definitely 9mm though. Both the USP, and p2000 that I have fired were in .40cal, and very ammo picky, never fully reliable.
Thought about a glock/xd/M&P/Sig?
Have gun, will travel.