Bet this river or take the free showdown? $25PLO

[Nitilism]

Villian is 65/0/3.67 (only 23 hands, though) at the time he bet the turn his Turn AF was 7 (yeah, I know, sample size... [img]/images/graemlins/confused.gif[/img])

Full Tilt Poker
Pot Limit Omaha Ring game
Blinds: $0.10/$0.25
6 players
Converter

Stack sizes:
UTG: $60.80
UTG+1: $26.80
CO: $29.85
Nitilism: $51.75
SB: $11.80
BB: $24.95

Pre-flop: (6 players) Nitilism is Button with K[img]/images/graemlins/spade.gif[/img] K[img]/images/graemlins/diamond.gif[/img] 4[img]/images/graemlins/spade.gif[/img] 4[img]/images/graemlins/diamond.gif[/img]
UTG calls, UTG+1 calls, CO calls, <font color="#cc0000">Nitilism raises to $1.5</font>, SB folds, BB calls, UTG folds, UTG+1 calls, CO calls.

Flop: 8[img]/images/graemlins/heart.gif[/img] Q[img]/images/graemlins/club.gif[/img] 2[img]/images/graemlins/club.gif[/img] ($6.35, 4 players)
BB checks, UTG+1 checks, CO checks, Nitilism checks.

Turn: 5[img]/images/graemlins/diamond.gif[/img] ($6.35, 4 players)
BB checks, UTG+1 checks, <font color="#cc0000">CO bets $4.75</font>, <font color="#cc0000">Nitilism raises to $17</font>, 2 folds, CO calls.

River: 3[img]/images/graemlins/spade.gif[/img] ($40.35, 2 players)
CO checks, <font color="blue"> Nitilism ??? </font>