What do you guys do in this situation? I find myself in it more often than I'd like to, and though I believe my decisions to be correct, it seems the other guy is always coming out on top.

$50 NL (FR)
I have on the button.
2 limpers, Villain raises to $3.50 from MP. I call, as does the SB and 2 limpers.

Flop ($19) is . Checked to PF raiser who bets $19. I am 90% sure he has AA or KK, and probably has a club in his hand. But I think he would also make the same bet, maybe a little smaller, without a club.
I push in for about $40, folded to Villain and he calls.

Do you lay this down? Are you worried about one of the 3 players left to act that checked the flop?

i call the flop and get it all in on the turn. if i'm first to act, i'll lead out in this case since its a pot bet (less actually). if i'm last to act, i'm raising all in. If you have deeper stacks and he's very aggro, you could check raise all in on the turn but if not, i would prefer leading out so he doesn't check behind and get a free card.

I really like the check here on the flop the only thing that sucks is that you and the PFR have players in between you. I am all in on this flop almost everytime. I totally disagree with waiting for the turn, Most players arent willing to put all their money in on a draw on the turn where someone with K might be willing to get it all in on the flop. Like everyone else said you are 2:1 to fill up. The chances of the PFR having the flush are small, if you check raise all in and one of the players in middle is slowplaying a flush you are going to probably have 2 other players all in and will be getting better than 2:1 on your money. If someone in the middle doesnt have a flush you are more often than not ahead.