The location in Monti is excellent, far enough from tourist attractions to feel authentic and have good restaurants, but close enough to be walkable. It was also a very good value and Simone was responsive. There were some minor issues: the bed was very very firm, we had to plunge the shower every day just to keep it from overflowing, and the front door is very thin which meant that you hear every time anyone is in the hall or going out the apartment building main door. The walls and ceiling were much better about keeping out the sound, so it was quiet most of the time. The washing machine was full of stagnant water when we first got there and smelled of mildew. So we bought cleaner and ran it with bleach to clean it, which did the trick. After that, the washing cycle worked fine, but the machine would go crazy on the final spin cycle, banging around very very loudly. We tried all sorts of different amounts of clothes (very few clothes, medium amount, large amount) and nothing made it work normally, so we had to go get them dried at the lavanderia down the street, as they were sopping wet and would never dry if we hung them up, which was our plan. Simone was responsive but didn't have any answers, as he seemed to not be in Rome and couldn't check it.
Our stay was very good, and a few tweaks would make this place truly excellent (and probably more expensive).