I think the key point to keep in mind is the rolling process is extremely slow. You're not rolling inches at a time, you're probably rolling millimeters / centimeter(s). Because of that it's not wrapping a bunch of sopping wet filter material around the cylinder. The part that just got pulled out will slowly move towards the cylinder, draining and somewhat drying as it goes.
I expected that water was going to whick up the floss, but it doesn't appear to. Exemplified by the unused side staying dry.
I just gave mine a sniff and touch. It doesn't smell bad. It smells a bit oceany, but I couldn't tell if that was just my sump smell. When I touched it, it feels cool, like it might be ever so slightly damp, but my fingers came away completely dry. My fingers did have a bit of that ocean smell, but we're talking pick up a log at the beach smell not skimmate.
Overall not something so far I'd be concerned about, particularly in comparison to a skimmer.