Great cozy place, very well connected to all the important tourist attractions.
Metro and bus stations are less than 5 minutes away. The metro line is the one that will take you directly to all the places that will matter - Vatican city, fontana di Trevi, piazza Spagna, the train station etc.
The Colosseum is 15 minutes away on a casual walk. There's a great restaurant just downstairs, but a lot of great options 10 minutes away or less.
Antonella was a great host, communication was perfect and she was super helpful.
The room was cleaned perfectly every day.
The only concern I'd have is if you are very light sleeper and want to sleep with the window open. The apartament is on a pretty busy street, so it can be pretty loud with the window open, but the windows are great and they block 90% of the sound - the only thing you'll be able to hear are ambulances or car honks directly below your window.
If you are traveling in the winter, I'd ask Antonella about heating options. We were there at the beginning of November and the nights were getting a bit cold, and the air conditioning barely did anything for us. I think during the winter you're going to need a bit more than that.
I'd recommend this place to anyone coming to Rome for the first time, and if we ever return we'll surely stay here again.