hmmm
both rims are good -- I've ridden w/ friends' rhyno lites before, and I am currently running mavics (819 disc, the new version of the 3.1). Both of those wheels may be a bit of overkill for you though, considering you stated you aren't doing any drops. I am 220, and occasionally do drops between 2-4 feet, and my rims have held up great so far. I'm not sure however, if they are available in 36h. this may be the deciding factor if not many companies have a 36h available in all their designs. again, both of the wheels you mentioned are good, but if you race xc, and only weigh 210, they may be a bit heavy when going uphill. Good luck!