Best in what price range? You can buy a small car for the price of a gun these days? I have shot RRA, Bushmaster, Armalite and some purpose built ANG Marksmanship Training Unit (All-Guard Team) guns. The MTU makes an awesome rifle, but you have to join up, shoot really good and try like heck to get one and then you have to give it back when you are done.
I have a personal Rock River that runs like a champ. The Armalite was about the same in quality and accuracy. Armalite customer service was better than average.
In the customer service area, there is a relationship between demand and service. Most gun companies could care less about service if they are selling well. The better they sell the less they care. Springfield Armory for instance has non-existant customer service and that is about as nice as I can relate my experience with them. They cancelled my ten gun order and closed our conversation with, "We really don't need your business, we have orders for the next two years."
I like good customer service and will pay a bit extra for it.