The apartment was exactly as described, clean, tastefully furnished, was fully equipped for cooking. The couch flips out into a full bed with a real mattress. Massimo was friendly and responsive, when we realized the coffee machine was broken, he replaced it within a day.
As others have mentioned, noise is the only potential downside. The windows don't seem to keep out street noise at all (I assume this may be typical of Venetian buildings?) - this was fine in our stay during the off season, but perhaps it's more of an issue when the real crowds are here in summer. And noise from the upstairs apartment is also fairly loud, if one gets unlucky and has e.g. a family with active kids running around until midnight.
Overall we loved our stay here and would happily come back for future visits.