I'm 230 lbs, and have about 4500 miles on my Giant OCR Limited (same frame). It is a very comfortable, excellent long distance bike - I have about 9 centuries on mine so far. The stock Xero xsr3 wheels were too flexy for my weight, so it's safe to assume they won't work to well for you, either.....

I resolved the issue by having a custom set made. Otherwise, it is a fantastic bike and I've no complaints at all. See if the LBS will either upgrade the wheels or made some other accomodation. It's a great bike and you'll love it.