Ok guys, help me out here. I have the chance to either get a factory 90mm MAS for my bone stock 00L or a Pro-M 80mm MAS. Which you be more helpful? I think the Pro-M would benefit more and the guy said it give him an extra 25 hp, but on the other hand the 90mm is larger. He said that the Pro-M has less than 3000 mi's and he paid i think around $250 to $300. What do think a fair price is for it? Any help would be great.