I always thought that the Metropolitan Vac'N'Blo was a wet/dry vac until I got it. Thankfully, I don't want to return it because I like it alot. Well, my question is whether or not it is safe to vacuum the carpet with the Vac'N'Blo after I spot cleaned and rinsed (with damp towels) the carpet? Also, how wet does a piece of fabric have to be before we really have to use a wet/dry vacuum?