The location is perfect - you can see the Colosseum from the window, 5 min walk to the metro station, a nice park and many good restaurants nearby.
The apartment is a mix of modern things (e.g. paintings, leather sofa) and old things (e.g. doors, bathroom), but overall is a nice and confortable one.
There is a lot of noise, but this is not an issues of the apartment, it happens in any location in Rome :) Andrea has kindly provided us good ear plugs which helped us to sleep well.
I recommend this appartment for its location.