The internal release group of these trackers are the best among other HD trackers. They are best on the net.

HDB:
Good 1080P/720P rip (They use a raffle system to determine which group could do encoding, so it's not always ctrl-hd, don, ebp)
Remux with info
TV episode is allowed
WEL-DL / internal ecoding TV episode (You can also find on BTN)
Only staff & vip could invite

AHD:
Good 1080p/720p internal rip
Good remux
No TV episode, only season pack allowed
No BD disk (will allowed on next version)
TV season remux
Only staff could invite, but have recruitment on other trackers, easier than HDB to join

So, If you like
BD disk - HDB
Movie encoding - either
Moive/TV Remux - AHD
TV episode - HDB