I bought a P220 used about 12 years ago and it has been nothing but sweet ever since. It had a lot of holster wear on it at the time so it must have been some LEO's carry weapon since CCW was still a pipe dream back then. I've put about 15,000 rounds through it and it's still going strong. Mine is very accurate and has been since day one. It's built like a tank too but not so that it shows up as too much weight. Mine has the aluminum frame from the "Made In W. Germany" models. It really is a great pistol.
I've never got to shoot the HK model mentioned. Can you give us an idea what kind of groups it does shoot? I'm not knocking you here. I'm just curious cause my Sig shoots mighty accurate. But like I said I've never shot that HK. I have shot other models. They were pretty accurate but not as accurate as my Sig. But that was about 12 years ago when I first got my Sig and I went to the range with the owner of the LGS where I bought it.
Well I have a full size .45 USP, and an Elite.45, I don't think you're looking for the Elite.
It doesn't matter much, both shoot as accurately as I'm able to fire a handgun.
Which is one ragged hole if I'm having a good day.
Your results may vary, I'm a Double Distg. shooter,(not trying to blow my own horn.)