freefall, another thought... do any of your buddies have an AR you can fire or can you rent one at a local range/gun shop? Why not handle a few in your gun shop and hopefully test fire a few. No sense buying anything until you're sure you like the platform.
Like MJ said above, why buy anything when you're a "virgin"!
Surely you can get a little experience before shelling out for a rifle you don't know.
BTW, earlier you said you were wary of S&W but they make a decent midrange AR. You might have been talking about their new Sport model which is stripped down but still ok. $699 is pretty high for the Sport, maybe it was an M&P-15OR. S&W makes a beautiful lower receiver and I bought one stripped for my first AR build.