I definitely love a4e with all their xdcc bots and quality releases, and I really liked Conclave's releases with Claymore and now Hayate no Gotoku but I'm not sure what's going on with them and mymenclave. They said it wasn't a merger but their site kind of makes it seem like it >.> Speaking of which I like mymenclave as well. They're doing an awesome job on Gundam 00 and did a great job with ef- A Tale of Memories.
I like Vegapunk for One Piece but their translator had a string of sick/exam/holidays so they're behind by quite a few episodes.
In regards to Dattebayo, their trolls can get to be a bit much but I don't think there have been any that really bugged me and I'd rather base my opinion on their continual release of fast quality subs for Bleach, Naruto and Genshiken 2 while it was still airing.
Really though there aren't any groups I would say I don't like, I've gotten shows from most of the ones mentioned and they all seemed fine to me except for some being rather slow or picking up too many projects such as Saizen atm (at least in my opinion).
