Bet the river or pick off a bluff?

[NotMitch]

About 15 hands into the session, no specific reads.

PokerStars 1/2 Hold'em (5 handed) converter (http://www.selachian.com/tools/bisonconverter/hhconverter.cgi)

Preflop: Hero is BB with K/images/graemlins/club.gif, T/images/graemlins/heart.gif.
UTG calls, MP calls, Button folds, SB completes, Hero checks.

Flop: (4 SB) 9/images/graemlins/spade.gif, A/images/graemlins/heart.gif, K/images/graemlins/spade.gif <font color="blue">(4 players)</font>
SB checks, Hero bets, UTG calls, MP folds, SB calls.

Turn: (3.50 BB) T/images/graemlins/diamond.gif <font color="blue">(3 players)</font>
SB checks, Hero bets, UTG calls, SB folds.

River: (5.50 BB) J/images/graemlins/spade.gif <font color="blue">(2 players)</font>

Hero?

[Schneids]

Bet and fold to a raise. Or if the opponent is extremely bluff happy call the raise.

If you're not comfortable doing that, then check and call.

I know I do both ways frequently enough though I think it's slightly better to bet.

[Guido]

I would bet out or check-call. About fifty-fifty I think.

Guido

[NotMitch]

Thanks for the comments, I felt this was a close situation, given that I didn't know much about the opponent. I couldn't think of a hand he could have with Q for the straight but he did play the like a lot of people would with a flush draw.

I didn't feel really good about the bet and fold to a raise line vs. an unknown, also since I was new to the table I did not want to encourage bluff raises in the future by folding. Also I wanted to see what he had. Betting and calling a raise seemed like throwing away chips so I checked, he checked, and MHIG. Hand history showed he has K2o, so I missed a bet.