I've got and built ARs from Del-Ton, DPMS, RRA, PSA and probably a few others. Personally I'd go with Palmetto State Armory, not only because they're a SC company, but because of the quality of their parts. Most of their barrels are FN (which is local to them) and everything is "mil-spec" which is actually a bit of a misnomer but that's another story. For standard triggers, theirs is better out of the box than most I've felt including a couple of so-called target triggers.
05 Tacoma TRD, SR5, V6, etc
1978 VW Westfalia
2007 Suzuki DRZ400s
Who is the happier man, he who has braved the storm of life and lived or he who has stayed securely on shore and merely existed?
Hunter S Thompson