Pay Off Here?

[TheOneWizard]

I was still new to the table at this point so I didn't have any reads.

Full Tilt Poker
No Limit Holdem Ring game
Blinds: $0.25/$0.50
6 players
Converter

Stack sizes:
UTG: $64.65
UTG+1: $41.05
CO: $45.35
Button: $79.10
Hero: $48
BB: $61.40

Pre-flop: (6 players) Hero is SB with A[img]/images/graemlins/club.gif[/img] 8[img]/images/graemlins/diamond.gif[/img]
UTG calls, 2 folds, Button calls, Hero calls, BB checks.

Flop: A[img]/images/graemlins/heart.gif[/img] K[img]/images/graemlins/club.gif[/img] 3[img]/images/graemlins/club.gif[/img] ($2, 4 players)
<font color="#cc0000">Hero bets $2</font>, BB folds, UTG calls, Button folds.

Turn: J[img]/images/graemlins/spade.gif[/img] ($6, 2 players)
<font color="#cc0000">Hero bets $6</font>, UTG calls.

River: 8[img]/images/graemlins/club.gif[/img] ($18, 2 players)
Hero checks, <font color="#cc0000">UTG bets $8</font>, Hero...?


I potted the flop and turn under the usual thinking that I had the best hand and needed to punish anyone who was drawing. Now after making Aces-up on the river and considering the underbet the general thinking is I should pay off here less I make myself completely bluffable. Yet in my experience at this level villain has the flush 100% of the time here. Should I save the $8?