Slowplay Bad, Raise Good!

Preflop: Hero is CO with K/images/graemlins/spade.gif, K/images/graemlins/club.gif.
UTG calls, 1 fold, MP1 calls, MP2 calls, 1 fold, Hero raises, 3 folds, UTG calls, MP1 calls, MP2 calls.

Flop: (9.40 SB) 5/images/graemlins/spade.gif, 3/images/graemlins/diamond.gif, K/images/graemlins/diamond.gif (4 players)
UTG checks, MP1 checks, MP2 bets, Hero calls...

Raising here is the right play and it's not even close. Right? I wasn't involved in this hand since I would have raised it without a second thought.

[numeri]

For a minute there, I almost thought this was me. I played a hand very similar to this tonight, but it was a rainbow flop. I could see it in that case. Here, we need to get our value from any flush draws that are out there now.

If the pot was smaller I would just call also, but in this hand when MP2 bets into the hero, if the hero just calls everyone behind him will be getting 11.4-1 to call, if someone has a hand like A4,A2,76, they are actually getting the correct odds to peal(they are 14-1 underdogs since the hero has a set so the 11.4 odds may not seem like enough but including implied odds if they hit, 11.4 is sufficient to make their call profitable) So It would be incorrect to slowplay in my opinion. Before one thinks about slowplaying they must ask themselves, if I just smooth call, can anyone behind me have a profitable draw that would not be profitable If I raised? If the answer is yes than it is better to raise right away. If there were 6-8 small bets in the pot after the hero smooth called then slowplaying would be correct since the hero now wants the gutshot draws to call since they are now calling incorrectly. Noticed I ignored the fact that there are possible flushdraws and OESD 's on this flop. This is becuz no matter what the hero does, raise or smooth call,these draws will still have a profitable call. A great advantage to smooth calling the flop is that the hero can charge the flushdraws/OESD's full price when he raises a blank turn and forces them to put in 2BB as a 4-1 underdog, but this strategy only has merit if smooth calling the flop doesnt allow someone else to make a profitable call.

[SoftcoreRevolt]

I'm raising, the coordinated nature of the board makes it likely I'll get people to call the raise now, rather than two BB on the turn. I'm especially hesitant to slowplay here since the turn raise could very likely fold out even the bettor, since it will scream I HAVE A SET to the timid. (Or to very weak hands.)