Your cousin will be fine. Do you know what year and what maverick version he will be riding? I checked them out at the iron horse website and they looked pretty nice. (Warning aggravating flash website, NSFDU (not safe for dial up )) I can't say I would recommend a dual suspension version, go with a hard tail if its not too late. That leaves you with the Maverick 1.0, 3.0, and 5.0. Looking at the 3.0 (only because its the middle model) you get a pretty decent set up. the front fork is adjustable but does not have a lock out. Your cousin may want to ditch that fork for one that he can lock out. Other than that, he may want to change the fat knobbies out for some slimmer semi slicks with a high PSI rating. He'll be ok, being less than 300lbs the only thing keeping him from riding is himself.

Bau