I was going to respond earlier - but I figured everyone else would, so I didn't bother (maybe everyone else thought this too - in which case we have a classic example of "bystander apathy"
)
You really can't go wrong with Bushmaster (although the price on the thing you linked to seemed pretty high).
I'd say the really good brands are Bushmaster, Eagle Arms/Armalite, RRA - and a bunch of others. As long as you stay away from the really bad ones (like Hesse - does Hesse even make ARs?) you should be fine. Colt are great too, but generally a little overpriced.
My personal recommendation is Bushmaster. Find an inexpensive dealer, buy one and have them ship it to a local FFL (you should pay no more than $30 to have a local FFL transfer it to you - no sales tax or precentages or any BS like that). I like Bushmaster because they have EXCELLENT customer service. I once sent back an AR to them because I didn't QUITE like the fit between upper and lowe. At their cost, they had it shipped back at their cost and replaced the upper. When I was still not happy, they had it shipped back at their cost again and replaced the entire rifle. Nothing was wrong with it - I just was slightly unhappy with the way it looked. I'm amazed at that level of cusotmer service. When I had to deal with armalite about ordering three parts from them, they fucked it up three times (on the same order, and tried to make me pay the resturn shipping every time when they had sent me the wrong parts). Those are just MY experiences, so they may not be a general representation.
Definitely shop around. There are some great stores out there. I always check quantico arms (I think their website is quanticoarms.com or something like that). I bought an Eagle Arms complete AR for less than $600 recently, and they are a great bunch to deal with.
(btw - as far as I know - the bayonet lug on a 16" carbine is kind of pointless, because I don't believe a bayonet will fit anyway, so that's not really a big deal. Experts please correct me if I am wrong).