I've built and bought, if I were going to war or knew my life depended on it I might buy a higher end factory gun known for milspec or exceeding milspec work. BCM, LMT, Colt, Daniel Defense, etc. If it were for hunting and fun I'd think about what I needed and build it or buy as close to what I wanted in the budget. I hate to not recommend top quality but you don't need it for plinking and hunting.
I hear the mid-level stuff is selling or sold at many local places but I haven't kept up. I sold a NIB bushmaster for $750 the other day, this was the Magpul version. I have one more if you want it but a Colt 6920 for $800 is a better gun.
Lube it good whatever you get, this is a great article by an expert: https://docs.google.com/file/d/0B20V...2&pref=2&pli=1