Im planning to do some loaded touring (rear panniers only), and currently have these wheels http://www.rosebikes.co.uk/article/xtreme-atb-wheel-set-28700-c-cross-wheels-474126/aid:474128 on my cx bike, and am starting to think the rear will not be up to the job at 28 spokes. Is there any problems with building road/touring rims, thinking the ones from spa, onto a mountain bike hub (need a disk hub)? also would 36spokes be overkill? Had a quick look around and cant find many ready built 700c disc wheels, any suggestions? Don't really want to spend more than £100. ill probably have a bash at building it myself.