Hi
Well with player like that (39/26 AF 2.8) you should consider also to 4bet your queens preflop.
Well as played of course you have to protect your hand VS possible flushes.
Also if he has flush already you have some outs to get your full-house.
So it is correct to play for stack here.
Board: Q
5
4
Equity Win Tie
BU 65.96% 65.96% 0.00% { QhQc }
SB 34.04% 34.04% 0.00% { KdKh }
Here is also example of what happen if he allready has flush on flop which is not very possible.
Not bad equity either.
Board: Q
5
4
Equity Win Tie
BU 34.44% 34.44% 0.00% { QhQc }
SB 65.56% 65.56% 0.00% { JdTd }
I wish you good luck at the tables.