PokerStars $50+5 SNG, how should I play AKs?

[HighStakesPro]

I welcome feedback from all SNG players or any tournament experts who wish to weigh in.

Five players left, top three get paid.

PokerStars No-Limit Hold'em Tourney, Big Blind is t150 (5 handed) converter

Button (t1015)
SB (t5560)
Hero (t4240)
UTG (t845)
MP (t1840)

Preflop: Hero is BB with K[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/spade.gif[/img].
<font color="#666666">1 fold</font>, <font color="#CC3333">MP raises to t1840</font>, <font color="#666666">1 fold</font>, SB calls t1765, Hero folds.

Flop: (t3830) 8[img]/images/graemlins/diamond.gif[/img], Q[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>

Turn: (t3830) 2[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>

River: (t3830) 4[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>

Final Pot: t3830

My reasons for folding were:

1. There are two short stacks left, which allows me to make greater use of my big stack by stealing everyone's blinds.
2. The players were playing reasonably tight, since it was close to the bubble, and I thought it was likely that I was up againnst a pair, which makes me an overall underdog to win the hand.
3. The other player in the hand was the big stack, the only player who could bust me.

Hand Quiz #48 in TPFAP presents a situation with some similarites to mine; I would appreciate feedback on whether my situation was close enough to make folding correct as it is in the hand quiz.