We stayed in Joseph's place on Vicolo del Cinque for ten days before and during Easter, and we loved it. The apartment is laid out with one shared living room and small kitchenette and then two bedrooms with their own bathrooms, so there was ample privacy for two couples or a family with children.
The check-in was smooth and the property manager Mel was on hand to help us when we couldn't open the washing machine door.
You are situated right above a very busy street of restaurants and bars, which was amazing, but also very noisy. Using ear plugs and closing the outside and inside shutters helped though and it wasn't too bad.
We'd definitely recommend Joseph's place if you're looking for a spacious place to rest after a long day exploring Rome (you're about a half an hour walk to most of the tourist attractions and there is a taxi waiting point right near the apartment).