Top Set on 3-flush flop

I have no idea how to play this. Not too many hands in PT on the participants, but I put their VPIP/PFR for what its worth.

FullTiltPoker Game #803934140: $0.25/$0.50 - No Limit Hold'em

Seat 1: Hero ($52.70)
Seat 2: MP1 ($47.85) (24/12 over 33h)
Seat 3: MP2 ($50.65)
Seat 4: MP3 ($21.75)
Seat 5: CO ($24.25) (31/11 over 35h)
Seat 6: Button ($39.10)
Seat 7: SB ($19.50)
Seat 8: BB ($50.80)
Seat 9: UTG ($24.85)

Hero is UTG+1 with :Qh: :Qd:

UTG bets $0.50, Hero raises to $1.50, MP1 calls, 2 folds, CO calls, 3 folds, UTG folds.

*** FLOP ***
:Qs:

(pot = $5.75)

Hero??

I lead for close to $5.

Maybe some more info. I wasn't sure what to do so I checked it.

Hero checks, MP1 bets $5, CO calls $5, Hero??

I lead for $4 or so. You know pretty much exaclty where you stand. Against 2 players you can fold (without drawing odds) to a turn spade so you want to encourage a high spade to make the mistake of calling a flop bet. At the same time you probably lose less (or draw out cheaper) on a made straight or flush this way.

The only real problem you have is if someone has the straight draw. Then they can stack you when they hit the straight and bluff you when they hit the flush.

Given the stack sizes i probably look to get it allin against all but the most passive of players if im raised. MP1 could easily be driving with the A and a little something else and im not folding top set for 50BB if CO starts getting aggro.