Top and bottom pair on 2-tone flop, get reraised?

[faman]

Don't have much of a read on UTG+1, I don't think I've seen him showdown a hand yet. I limp from the button with A4s (questionable? I like seeing flops cheaply with suited aces)

Ultimate Bet No-Limit Hold'em Tourney, Big Blind is t40 (8 handed) converter

saw flop|<font color="C00000">saw showdown</font>

<font color="C00000">UTG+1 (t905)</font>
MP1 (t390)
MP2 (t1200)
CO (t1720)
<font color="C00000">Hero (t955)</font>
SB (t1345)
BB (t1065)
UTG (t2420)

Preflop: Hero is Button with 4[img]/images/graemlins/heart.gif[/img], A[img]/images/graemlins/heart.gif[/img].
<font color="666666">1 fold</font>, UTG+1 calls t40, <font color="666666">3 folds</font>, Hero calls t40, SB completes, BB checks,

Flop: (t160) J[img]/images/graemlins/club.gif[/img], 4[img]/images/graemlins/diamond.gif[/img], A[img]/images/graemlins/diamond.gif[/img] <font color="blue">(4 players)</font>
SB checks, BB checks, <font color="CC3333">UTG+1 bets t40</font>, <font color="CC3333">Hero raises to t280</font>, SB folds, BB folds, <font color="CC3333">UTG+1 raises to t520</font>, <font color="CC3333">Hero ...</font>


I flop top and bottom pair, and decide to come over the top of UTG+1's min bet with a pot sized raise. This smells like an overplayed flush draw to me (see a lot of those at this level, $5.50 UB), but as I said I don't have much of a read on UTG+1. I'm not quite pot-committed yet, as I'll have about 600 left (at 20-40 blinds) if I lay it down here. Your move?