Anna has just been a great host. Available at any moment (she lives in the next door apartment), from the arrival in Rome until we left the apartment. She allowed us to leave our luggage to visit the city until the last moment, and was very helpful (tips and tricks, addresses, etc). The apartment is huge and very clean, well equipped, to make it short: it was a great choice :)
Regarding the location, it is 5 minutes away from the "Euclide" railway stop, which connects to the Flaminio metro stop. You should expect a 25-30 minutes trip to be in the historic center, which is very nice as well.