50 NL Two Pair, turn decision

[Sphere99991]

This is the first hand against this guy, so no reads, I've never played him before. Basically, what is our turn play?

Poker Stars, $0.25/$0.50 NL Hold'em Cash Game, 2 Players
LeggoPoker.com - Hand History Converter

Hero (SB): $50
BB: $30

Pre-Flop: 6[img]/images/graemlins/club.gif[/img] A[img]/images/graemlins/club.gif[/img] dealt to Hero (SB)
<font color="red">Hero raises to $1.50</font>, <font color="red">BB raises to $2.50</font>, Hero calls $1

Flop: ($5) 6[img]/images/graemlins/diamond.gif[/img] A[img]/images/graemlins/heart.gif[/img] 4[img]/images/graemlins/diamond.gif[/img] (2 Players)
BB checks, <font color="red">Hero bets $3</font>, BB calls $3

Turn: ($11) 8[img]/images/graemlins/club.gif[/img] (2 Players)
<font color="red">BB bets $5</font>, Hero ???

I do not think folding is an option, so the question is do we smooth call or raise? He has about $20 behind after his $5 bet. Both have merits: obviously if he is bluffing he'll fold to a raise, whereas if he has a good hand there may be a lot of turn scare cards.