Well, I bought the AR-15. I went with the Bushmaster XM15 E2S, 20" barrel, free-floated, flat top receiver.
The rifles are built right here in Maine, so that had something to do with my decision.
I like the idea that the Bushmasters are chambered for the 5.56 and the .223, so it is built to Military specs which is the higher pressure. Also, I haven't heard anything bad about the Bushmasters, unless someone complains of price. But then again, Armalite and Colt are more expensive.

I'll post later of the accuracy of this rifle. It is supposed to arrive today.

If you ever look at the prices that Bushmaster lists, don't be scared away by their MSRP's of their rifles. I found several distributors on the net that saves you a couple of hundred dollars on most of the rifles.