This was the perfect accommodation for our family of five for our trip to rome. It is a spacious appartment with beautiful tiled flooring.
Michele was very forthcoming and enabled an early check-in without any surcharge, which was very helpful because we arrived in the morning.
As far as the location is concerned it probably doesn't get much better than that.
We did most of the sight-seeing on foot. St. Peter's, the Vatican Museum, even the city center accross the river is within 30 min walking distance and what enjoyable walks are these, because on virtually every corner there is a monument, a palazzo or a beautiful piazza.
We took the occasional bus ride (line 280 stops just around the corner and takes you to Trastevere - 9 stops).
The Metro (Lepanto) is just a 3 min walk from the appartment, but we only took it on two occasions, for example when we were going to the Colosseum.
We only bought single fares for € 1,50 each (children under 10 do not pay), so we ended up spending less than € 30 on public transport for three adults for a period of five days which is considerably less than buying 3 day passes.
One last word on getting there. We booked "SIT Bus" (on-line booking in advance highly recommendable) which stops nearby i.e. a 10 min walk to the appartment)and you don't have to take a detour via Termini main station.