I have a 9m HK USPc. I hard chromed the slide. I love that gun. Admittedly, it is a fullsize grip with a shorter barrel - and I do not shoot as well with it as 4"+ barrelled guns... Probably the sight radius - as I always have this problem with sub 4" barreled guns.
Anyway - it is a great gun. I did have a fullsize USP 9mm, but I sold it to buy my fullsize P99 - as the grip was a bit large for my hands. I kinda wish I still had that USP, however.
I wanted a 45 ACP USP, but the grip is even bigger - too big of a gun for my hand.
The HK45 and P30 looks very sweet. And, as the compacts have a smaller grip that isn't as fat - 1 day I may have to get a 45 USP compact.