The apartment was exactly what we needed, perfect for two couples - two bedrooms, a fully-equipped kitchen with a small balcony and a spacious bathroom, working air conditioning in both bedrooms.
The location is great for Rome sightseeing, 4 minutes to the metro, just a couple of stops from Termini, plus the buses on the other side of the street.
The check-in process was easy, Marco let us drop the luggage on the day of arrival at 10am which was perfect so that we would not carry it to the city center after a early morning flight. The communication with Marco was excellent, his mom who did the check-in showed us tips for the local restaurants, shops, etc. and even left us tiramisu dessert in the fridge :-)
Only issue was with the shower, which needs a very gentle touch as you either end up with a freezing cold or steaming hot water if you are not patient enough, but it's perfectly manageable once you get used to it.
Overall - the best apartment I've stayed at in Rome so far - reasonably priced, location near the metro, safe neighborhood, air-coned, amenities.