I like both my G19 (Gen 3) and my USPc .40. Both have been good reliable guns.
I think it comes down to what you really want. Do you want a striker fired pistol, or a hammer fired pistol? Do you want a manual safety? How good are you with the DA to SA transition, or do you want to carry cocked and locked?
Keep in mind that magazines for the HK are going to generally be more expensive as well. I try to buy all my HK magazines lightly used off the forums.
The brass to face issue with the Gen 4's seems to happen with some pistols and not with others. But one thing is for certain, it will not happen with the HK.