So far, I have always gone with hand built wheels and have never had problems. For the mountain bike, I use Chris Kings with Stan's Arch rims (about the lightest I'd go) and they have held up well. I am a smoother rider (and have been as high as 188) but I'll fly off 2-foot drops smoothly and go through fast rocky descents at speed while picking lines. I would not do any real rough stuff with this bike...just gravel roads. That is why I was hoping to stay light- maybe a 28x28 if hand built with a DT 29er light rim or something like the C2s. I see your concern though, and need to look at rim options, in case I go hand built.