50NL: AQs in the small blind vs active stealer

[RapidEvolution]

Villain is 21/18/3 over 220 hands and has a 47% att to steal.


$0.25/$0.5 No Limit Holdem
9 players
Converted at weaktight.com

Stacks:
UTG (<font color="#0000cc">$48.65</font>)
UTG+1 (<font color="#0000cc">$72.50</font>)
MP1 (<font color="#0000cc">$39.50</font>)
MP2 (<font color="#0000cc">$49.50</font>)
MP3 (<font color="#0000cc">$20.00</font>)
CO (<font color="#0000cc">$38.35</font>)
BTN (<font color="#0000cc">$51.60</font>)
Hero (<font color="#0000cc">$50.00</font>)
BB (<font color="#0000cc">$61.00</font>)
[MP3 posted $0.5]

Pre-flop: ($1.25, 9 players) Hero is SB A[img]/images/graemlins/spade.gif[/img] Q[img]/images/graemlins/spade.gif[/img]
<font color="#777777">4 folds</font>, MP3 checks, <font color="#777777">1 fold</font>, <font color="#cc0000">BTN raises to $2.25</font>, <font color="#cc0000">Hero raises to $7.75</font>, <font color="#777777">1 fold</font>, <font color="#777777">MP3 folds</font>, <font color="#cc0000">BTN raises to $24.25</font>, <font color="#777777">Hero?</font>

With such a high steal% I felt 3betting with AQs was for value. However, I've never seen him 4bet preflop before . If I'd had AK, I think I would've had no problem shoving, but with AQs, I think it was really marginal. Am I being too nitty here if I fold?