On this flop, with 7 outs to improve your hand (7,q or 10h)and 19 that could stop you (a,k,j,spade), I'd try to take the pot right there and donk bet it. You're ahead of a lot of people's cutoff ranges, the chances of one of them having a single spade here are far, far higher than the odds they've got a made flush. So unless you're pretty sure the CO will c-bet then you have to bet yourself. Can't let someone outdraw you for free.

Because this is a three way pot, it needs to be a pot sized bet or you'll be giving your opponents correct odds to draw to a flush. This only has to make them fold 50% of the time to be a breakeven play, and a lot of hands are folding here. If you get raised, it's gonna be a made flush or overpairs, or someone holding the ace of spades. You'd need a lot of ballas to bluff at a monotone flop without a holding, so if the CO raises you, give him props.

Please someone tell me if I'm wrong here, but I'd be PSB-ing this against a hell of a lot of opponents. Or is that a losing play?