We had a great experience with Momo. We're familiar with Rome and the Campo de Fiori area, and Momo's apartment was perfectly located for our needs (easily walkable to Piazza Navona and the Pantheon in one direction, and Castel Sant Angelo in the other; it was also 2 minutes' walk from a taxi station and buses on Corso Vittorio Emanuele as well as a small Pam supermarket.) The excellent and popular Roscioli and Emma restaurants, fried cod from Dar Filettaro a Santa Barbara and pizza bianca or rosso from Forno Campo de Fiori were literally steps or just a couple of blocks away.
The apartment was very spacious, sparkling clean and exactly as pictured. Momo's check-in instructions were very clear (she even sends photos so you know exactly what to do) and she was very responsive to messages (e.g. we asked about where to take our trash and she was quick to respond).
It's not easy to find an affordable, comfortable 2-bedroom rental in this central a location. We'll gladly return!