What kind of quality will the T-shirts be? I love the Haines T's, very good quality. Count me in for a Large in the Navy either way though.
From what I have seen in past Group buys, so you don't get stuck footing the bill and having boxes of these left over, I'd make people prepay before you send official #s to the printer. I just hate seeing people get burned on left-over stock.
Oh and let me just say, thanks for all the work you have done latley in getting the troops rallied toward the cause.