Their is a fella at m4carbine.net who put together a matrix of AR features catagorized by manufacturer it may help. I roll my own so to speak so my opinons are biased but I don't care for Colt products or the uber expensive Noveske type guns. I still remember when Colt was droping out of spec garbage on the commerical market and hiding behind their reputation. I have seen alot of Bushmasters perform very well providing the gas key is staked. Cav Arms makes good guns that are hard to beat price wise. I don't like Olympic Arms or DPMS. That being said I shoot the **** out of my guns and bang them around alot so my needs are diffrent than somebody that wants to plink. For anybody thay wants to build their own I reccommend M&A parts kits and Spike's Tactical Lowers.