200 NL - TPTK in BvB, turn decision

[janh]

Villain is 18/14/2.7 over a large sample. His fold to cbet is 48. He has open pushed the turn with his AK into my overpair on a 9974 board once.

Titan No-Limit Hold'em, $1.00/$2.00BB (Titan HH Converter by Kreatief)

CO ($197.00)
Button ($208.32)
SB ($228.00)
BB ($210.65) (Hero)
MP2 ($186.30)
MP3 ($125.35)

Preflop: Hero is BB with A[img]/images/graemlins/club.gif[/img], J[img]/images/graemlins/heart.gif[/img]
<font color="#666666">4 folds</font>, <font color="#CC3333">SB raises to 6.0</font>, <font color="#CC3333">Hero raises to 20.0</font>, SB calls $15.00,

Flop: J[img]/images/graemlins/diamond.gif[/img], 9[img]/images/graemlins/spade.gif[/img], 2[img]/images/graemlins/diamond.gif[/img] ( $44 )
SB checks, <font color="#CC3333">Hero bets $28.00</font>, SB calls $28.00,

Turn: 5[img]/images/graemlins/club.gif[/img] ( $100 )
SB checks, <font color="#CC3333">Hero checks behind or bets $70ish?
If we bet, does Villain crai weaker hands or are we getting stack-a-donked?
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Thanks!