Nowadays, I'd say that was as smokin' deal.
As for the caliber, unless you have a specific need for a larger caliber, go with .223/5.56mm so you can afford to shoot it and have the largest selection of accessories. Same thing for the barrel; if you have no specific need for a heavy barrel, get a light one (the lighter the better, IMO). I'll offer similar guidance on the barrel's length; unless you need a certain longer length for velocity or shooting competition reasons, go short. It'll bounce a bit more when fired, but it's not like that caliber is gonna brutalize anyone. Short (16"), light, and handy in .223/5.56mm semi-autos is the way to go, IMO.