Scary river card - check behind a good play?

[spacemonkey57]

Villan is loose passive, but I still didn't see any way I could bet that river with a four flush and a pair and an overcard on the board. Should I have bet it anyway? Thanks.

Party Poker 1/2 Hold'em (9 handed) converter (http://www.selachian.com/tools/bisonconverter/hhconverter.cgi)

Preflop: Hero is BB with Q/images/graemlins/heart.gif, Q/images/graemlins/spade.gif.
<font color="666666">2 folds</font>, MP1 calls, <font color="666666">3 folds</font>, Button calls, <font color="666666">1 fold</font>, <font color="CC3333">Hero raises</font>, MP1 calls, Button calls.

Flop: (6.50 SB) J/images/graemlins/diamond.gif, 3/images/graemlins/heart.gif, 3/images/graemlins/diamond.gif <font color="blue">(3 players)</font>
<font color="CC3333">Hero bets</font>, MP1 folds, Button calls.

Turn: (4.25 BB) 9/images/graemlins/diamond.gif <font color="blue">(2 players)</font>
<font color="CC3333">Hero bets</font>, Button calls.

River: (6.25 BB) A/images/graemlins/diamond.gif <font color="blue">(2 players)</font>
Hero checks, Button checks.

Final Pot: 6.25 BB
<font color="green">Main Pot: 6.25 BB, between Button and Hero.</font>

[Yobz]

I might have this wrong, but I've heard that a good rule of thumb is this:
If you are going to check/call then bet and if you get raised, fold.
If you are not willing to call a bet then check/fold

[Yobz]

Let me also say this: if you think the opponent has a chance of laying his hand down then you might want to try and bluff (if he has a good chance of laying down). If you are sure that you are beat and/or your opp is a calling station then check/fold

[Chris Daddy Cool]

is your opponent a bluffer? will he bluff raise the river often? the more tricky/aggressive the guy is the more i'm inclined to checkcall. the more straightforward this guy is i'm betting this river, and folding to a raise.