We were 5 people and stayed for 4 nights. Great location (we could reach the sights by foot, supermarkets were near, also a lot of nice places to eat and drink in that corner), very nice and spacious apartment (perfect for 5 people), flexible Check-in Check-out hours, Rudi answered very fast and was always reachable.
I would definitely recommend it!
What could be improved is the wifi, the speed was really low- we could not really use it. Also the water pressure was not the best- but I think this is a general problem in Rome.