The two boats would give you significantly different rides. The shorter semi-displacement hull of the R-25 would be comfortable in choppy water, but would "hobby-horse" in a head sea. The Nimble Wanderer would handle a head sea much better, but would be somewhat rolly in a beam sea with its more rounded bilge. If it is the motorsailer version, the steadying sails would definitely help in this regard.
If seas got very rough, I would rather be in the larger Nimble with its added ballast, and a hull designed by the respected Ted Brewer.