[GeoffM]

Actually, it sounds as though I would have played the same exact way. He had less outs than you for his straight after the turn. Anytime you flop top set, you gotta make sure as many chips as possible go in. If he had QJ, he had 4 aces and 4 10s. But if the board paired, you would have taken down a huge pot. Of course, he may have had the wrap (AQJ, or even AQJ9 or just QJ9), but you still have to put in chips because you are indeed ahead. One thing about a O8B MTT, same as hold'em, you have to be able to win a coin flip hand, and the coin was in your favour since your hand was already made.

You also had A2 for the nut low draw. However, in this care you actually want the board to pair. You didn't do anything wrong this hand. You had 6 outs after the flop and 9 after the turn, just got really unlucky.