Folding a Big Hand Late

[phy1234]

You are at the final table of a 500 person $20+2 on PP. You are second in chips and you finally get a real hand. Then crazy action takes over.I have played with the big stack for over 100 hands and he has not done anything crazy. He has been big most of the time and has not gotten out of line. Is this an easy call or a tough fold. (Playing to win not 3rd)



Party Poker No-Limit Hold'em Tourney, Big Blind is t6000 (9 handed) converter

Button (t86919)
Hero (t84047)
BB (t51243)
UTG (t83901)
UTG+1 (t37160)
MP1 (t103969)
MP2 (t13616)
MP3 (t35695)
CO (t23450)

Preflop: Hero is SB with K[img]/images/graemlins/heart.gif[/img], K[img]/images/graemlins/diamond.gif[/img].
<font color="#CC3333">UTG raises to t20000</font>, <font color="#666666">3 folds</font>, <font color="#CC3333">MP3 raises to t35695 (All-In)</font>, <font color="#666666">1 fold</font>, <font color="#CC3333">Button raises to t86919 (All-In)</font>, Hero???