Pros: Good communication from hosts and decent location relatively close to the Vatican and some very nice places to eat (try Lattuga), get a coffee (Artigiano del Caffé) or have a gelato (Manny's Gelateria) . Most of the items in the room are new and you get your own air conditioner and a small balcony.
Cons: Location is 20+minutes by bus to the other side of the river and 45 minutes to the central train station (take #70). Listing says it includes breakfast and, I guess you can make a case that it does, but you should know that what is included for breakfast is a packaged muffin, child's juice box and a pod coffee. Neither particularly healthy nor filling in my opinion. The host says that they can't serve food because of a license issue so calling this a bed and breakfast is misleading. If you book through Booking then you can add a voucher to a restaurant but I'm not sure what that cost. I ended up eating out for my meals so it cost a few euros more than I expected.
Other stuff:
Not well publicised is the fact that you are very close to a gorgeous overlook. Look for La Terrazzee on the G maps. I went up in the morning and really enjoyed the view of the Vatican and Rome Central and was truly amazed by the scale of the Piazza Venezia which looks enormous! I'm assuming the night view is great from the photos online but be prepared for lots of people on the weekend as evidenced by the beer bottles everywhere
I would not recommend leaving the air conditioner on all night as the room is v small and it blows on you the whole time. Better to use it to cool the room then open the porch for fresh/cool air (at least in August).