I would say Spikes is really good- if you can afford it... Noveske makes some really nice rifles (or riffles if you're nynco :P ) and I currently have a POF P415 which I love- but it's a piston system and some aren't really fans esp since it raises the rail a bit by comparison to DI. I have friends who have DPMS and they say they're pretty good. I personally agree with Robby- Colts are good, but there are better out there, and the Colt is really more for name dropping and historical value. I put my seal of approval an POF, Spikes, Noveske, LWRC and haven't heard anything bad about BCM... also the Barrett AR I shot recently is pretty nice- but the price is a bit higher than I'd actually pay.