Heres my $0.02:
Have had this for a few months now, shoot it VERY frequently (about 400 rounds a week).
Well over 2k rounds now. Zero malfunctions.
I like it a lot. Grip/trigger are the best parts, the gun sits and points so naturally. The charging supports are kinda cool, overhand rack is my preferred method and they make this nice. Shoots like a dream. Light recoil, excellent accuracy (certainly outshoots me), and the trigger is way better than anything comparable (Glock, M&P). It has a clean and consistent break and a short, clear reset. I've never noticed the blade in the trigger or the trigger groove, but a buddy of mine was not a fan of the blade.
I'm not without my gripes.
Mag release is one- get used to it seems to be the only answer. It will be confusing at first (anyone I've let handle it commented on this first, nobody was sure what to do- index finger? Thumb?). I got used to canting my grip to use my thumb. Works for me.
Mags are another. Not that they aren't good, just that they don't exist. They are rare and expensive. Even more so in ban states. You can forget factory 10-rounders. I managed to beg my dealer for a third converted factory 15 (modified follower to limit to 10), and it came with two set up the same way. I'd prefer factory 10's but cannot find them.
Sights are the last woe. They are OK. Serviceable. Nothing wrong with them, they just could be a lot better.
All in all though, wonderful gun. All of the praises, glory unto HK, and all that jazz.