G unit is crap, top to bottom. 50, Banks, Yayo, and buck all are pure shit, through and through. I can't understand why everyone's on Banks' dick right now. He hasn't spit 1 line that's impressed me. Ever. That's amazing(ly inadequate), considering that I've been impressed by 1 or 2 lines here on RB.com.
D block's ok. Jada's tight, Styles is average and Sheek is pretty much crap, he'll spit 1 hot line for every 10 songs he records.
So the question boils down to Crap(g-unit) vs. OK(D-Block). I'll go with OK.