People are towing cars on trailers, why not some quads? I don't think they will be a problem, but again, as was mentioned, usually these rigs are pretty close to their weight limits.
Look around at the various brands, as some seem to manage the weight better than others.....heck, some are to the point that if you bring the family cat, you're overloaded!!:S
Also keep in mind, MHs are usually not very off-road ready....so you may find that you won't get to the same places you might have gotten to with your TH and truck.
