Yep. Same with the AAC FH I am going to be tossing soon.
Originally, I planned on going with the M4-2000 but never did. Since I'm not in on that suppressor, I am going with Surefire and getting a closed FH. Oddly I never noticed it on the AR-180 or at least not as bad. Nothing against 3 prongs but the twang can be annoying at times. Then again so can the sproing of the buffer spring. I just would rather have a closed FH.
I sort of think that the 3 prongs maybe should stay in the 60s.
YMMV
ETA: That might seem a bit harsh and controversial but I won't reverse myself. I understand the concept of 3 prong but if I had a choice it would be closed. It's not the twang as much as things hanging up on it.

