200NL - FD 3way pot, deep

[Bramsterdam]

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

<font color="blue">Reads: IR is a regular playing 17/15 after 1k hands. Positionally aware, but a little bit weak. BB is also a regular, 21/19 after 550 hands. We respect each others games. He has 4b me with air before, not really important for this hand.</font>

CO ($192.00)
Button ($440.00) (Hero)
SB ($262.05)
BB ($197.00)
MP2 ($579.70)
MP3 ($178.95)

Preflop: Hero is Button with 7[img]/images/graemlins/diamond.gif[/img], A[img]/images/graemlins/diamond.gif[/img]
<font color="#CC3333">MP2 raises to $7.00</font>, <font color="#666666">2 folds</font>, Hero calls $7.00, <font color="#666666">1 folds</font>, BB calls $5.00,

Flop: 8[img]/images/graemlins/club.gif[/img], J[img]/images/graemlins/diamond.gif[/img], 4[img]/images/graemlins/diamond.gif[/img] ( $22 )
BB checks, <font color="#CC3333">MP2 bets $20.00</font>, Hero?

My standard play is to pitch it pre-flop, but 200BB deep I figured Axs was good enough to defend my button with. I'm not familiar playing 200BB deep, so this might not be very interesting.

What is the best action on the flop?