common spot vs nit

[bubaloo]

villain: 19/9/0.7 (70h) (seems nitty ldo)

Pacific Poker
No Limit Holdem Ring game
Blinds: $0.5/$1
6 players
Converter

Stack sizes:
UTG: $24.2
UTG+1: $95.5
Bub: $106.84
Button: $23.23
SB: $160.93
BB: $135.34

Pre-flop: (6 players) Bub is CO with A[img]/images/graemlins/spade.gif[/img] K[img]/images/graemlins/spade.gif[/img]
UTG calls, <font color="#cc0000">UTG+1 raises to $5</font>, <font color="#cc0000">Bub raises to $17</font>, 4 folds, UTG+1 calls.

Flop: 6[img]/images/graemlins/club.gif[/img] J[img]/images/graemlins/spade.gif[/img] 7[img]/images/graemlins/diamond.gif[/img] ($36.5, 2 players)
UTG+1 checks, Bub....?

what are your thoughts on 3betting vs calling him PF?

what are your thoughts on Cbetting vs checking behind?