We loved this apartment. It is ideally situated in the Trastevere area, which is the best place to be in Rome for bars and restaurants. A very bohemian atmosphere.
Getting to all the main tourist attractions during the day is an easy walk over one of the bridges. At night you will not want to leave Trastevere.
The apartment itself is very clean and very traditional which we loved. So much better than a nondescript hotel chain.
The private rooftop terrace is ideal for a G&T before heading out at night.
Mario is very helpful but unobtrusive.
Take the transfer from the airport via Mario as this takes all the stress out of the transfer.
I can recommend this as a great choice.