We enjoyed our stay at the Loft dell'Arte which is truly a unique travel experience. The apartment is located in a very quiet, residential area where on-street parking is easy to come by and SAFE...a big factor in Rome. You're only a five minute walk from the Furio Camillo metro station which is on the A line that connects you with the Vatican (about a 30 minute ride); you're also a ~15 minute walk to the Parco Appio Antico where you'll find a nice green space for running or biking. The neighborhood has several good restaurants and is away from the hustle and bustle (and the throngs of tourists) that you find in the historic center so, if you want to spend time with normal Romans during your stay, this is a great way to do it.
The apartment itself is very nicely decorated in a modern style and you have all the important comforts including A/C, wifi, cable TV and washing machine. Definitely large enough to comfortably accommodate a family of 4 or 2 couples - although the apartment has a futon that could sleep an additional 2 ppl, I'd think it could get a bit tight (especially with only 1 shower).
Finally, I want to say that Sebastiano is a great host! He is responsive at all times and committed to making sure your stay is enjoyable.