Welcome to 2+2!

Grunch (I'm providing my thoughts prior to reading any other post):

First of all, raising 99 to a no read UTG open raise is very -EV at almost any level, and certainly at .25/.50 and up. I fold this hand. That said, if you do think he's on tilt, I call the bet only if I'm continuing as I don't like 99 capped. [img]/images/graemlins/frown.gif[/img]
On the flop, you must bet to see where you stand. If MP# calls and UTG raises, then I fold. 99 only beats 2 bluffs, and the calls from MP3 indicate that at least one of them isn't bluffing. I think you are behind most of the time in this situation, and can avoid it altogether by folding pf.