Fun w/ A8s

[The Dude]

Bellagio 30-60, 8 handed. UTG is loose and passive and bad. SB is very good preflop and postflop, and certainly capable of 3rd level thinking.

Preflop: The A[img]/images/graemlins/heart.gif[/img] is exposed and replaced during the deal.
UTG limps, folded to The Dude who raises A[img]/images/graemlins/diamond.gif[/img] 8[img]/images/graemlins/diamond.gif[/img]. SB 3-bets, BB folds, UTG calls, The Dude calls.

Flop: (10 SBs) A[img]/images/graemlins/spade.gif[/img] Q[img]/images/graemlins/club.gif[/img] 6[img]/images/graemlins/spade.gif[/img]
<font color="blue">(3 Players)</font>
SB bets, UTG calls, The Dude raises. SB 3bets, UTG folds, The Dude 4bets. SB calls.

Turn: (9.5 BBs) 4[img]/images/graemlins/heart.gif[/img] <font color="blue">(2 Players)</font>
SB checks, The Dude bets, SB calls.

River: (11.5 BBs) T[img]/images/graemlins/diamond.gif[/img]
SB checks.

Does The Dude have a value bet here?