There are plenty of H&K fanboys, but I think there are even more haters.
I've got a USP 45 with a stainless slide. I bought it used but like new for a reasonable price because it is set up for a lefty (I am left handed too). It has the traditional DA first shot, single action follow up and can also be cocked and locked. DA first shot is a little stiff, but no worse than my CZ85 (I have an early one, I think it is called a pre-B now). Single action is pretty good on my USP.
The H&K USP 45 is big, but no less than expected for a high cap .45. When I first got it, I had the sensation like the gun wanted to slip out of my hands, but after shooting it the first time the feeling went away. I am very happy with the accuracy.
I had one experience with H&K Customer Service - the weld snapped on one of my mags, so I contacted H&K and they had me send it back. Not only did H&K replace the broken mag I sent them, but they also rewelded my broken mag and returned it too.
I'm not sure how the current prices compare for a new H&K vs other brands, but if you can find a new or used one for a reasonable price, they are worth looking at, especially if you want a hammer fired polymer gun, as there are not too many examples out there (FN has one, not sure who else).