This place was great. It was in such an ideal location. You are right in the heart of things, but not overly touristy. You are basically in the Campo di Fiore, which is really cool (good restaurants, bakeries, shops, etc).
The apartment itself is nice. It's big enough to not feel cramped. It has pretty much anything you might need. The washing machine was especially helpful for us, since we went on a muddy bike tour our first day and got quite dirty. But it's important to know that there isn't a dryer.
The bed is comfortable, but be aware that it is located on the top loft, which can only be accessed by a very steep/narrow spiral staircase. It is not a big issue, but it could be a problem for people with mobility issues. There is a second bed area on the main floor, but the this bed is not as nice.
The bathroom is clean and big.
The kitchen is set up to be able to cook, but we never used it in that way, so I can't speak to how good it is. The fridge was big and kept or drinks cold.
I would easily stay here again.