In practical terms, I don't think you can make cotton suck liquids out of a tank (vertically) like mesh can. Some do set them up as so-called auto-drippers with cotton, tho. Nothing wrong with that. (Philosophically speaking. Religiously speaking it's utter blasphemy.)
Other than that it's just my personal opinion on the matter. I wouldn't buy a gennie to set it up with cotton. I imagine other atties, built for the purpose, may do a better job. Primarily thinking of the more recent KFL evolutions like the Erlkonigen and Squape R. If you already have a gennie collecting dust due to a dislike for cotton, on the other hand....