Its much easier to put a lethal amount of hits on someone at 30-60 meters now than before - with attachments. I think this is good. It now makes much more sense to choose them over other carbines if you like to engage at range.
The Razor is astonishingly good now, and the X11 has finally been brought in line with the DMR. Our close in carbine got hosed this patch, but who cares grab a Cyclone - with a grip! It's even better now too!
Used the AC-X11 again last night but not for long. I noticed it soon went through it's unfeasibly small clip, but nothing else. What's changed? Ahh. Just checked. So less recoil and faster HV ammo, plus less reload. Hmmm.
Unknown, and probably never will be. Until GU8 nobody knew the exact figures as to what the compensator did and that was just a flat 5% it turned out. Now it's different gun to gun and much more complicated. I don't actually use HVA on my Razor anymore because of how stupidly accurate it is without it. A bit more leading and a bit less damage at range sucks, but landing 80% of your shots at 40m doesn't. Either way works. I recommend the HVA for the X11 - it's optional for the DMR. X11 definitely needs more zip on its rounds.