If you are any sort of handy and dont care about resale value I say build your own from Model 1, M&A, JT Dist, or even Deltron. Usually you save quite a bit of cash and you get exactly what you want.
Otherwise
Rock River
Bushmaster
DPMS
Armalite
Stag
Doublestar
all make nice ARs. Just never buy anything with Hesse, Blackthorne, or Vulcan on it.