The apartment is absolutely amazing - about 1 block away from the Colosseum, close to the metro and to bars and restaurants. The space was large, clean and was really great.
The one problem we had was with the check in and check out process. Upon arriving, we had to wait half an hour for someone to come let us in. This was apparently because the person who was originally checking us in had an accident so we didn't mind waiting.
Check out was a completely different issue. Apparently the company renting the apartment needs to send someone to check on the apartment the morning you leave. By itself that is not a huge deal - I figured they wanted someone to make sure nothing was damaged, etc. They asked when we were leaving - I said around 10:30 am (checkout at 11). The next morning someone came by at exactly 10:30 and it turned out they not only wanted to check the apartment but expected us to leave at that time. I have stayed at dozens of Airbnbs and have never ever encountered a situation where I was expected to state an exact time of departure to the minute. My wife was not ready and we had to ask the guy to come back in 15 minutes. Folks who rent airbnbs are typically travelling and it is incredibly inflexible to expect someone to check you out in person.
Overall 5 stars for the apartment but the check in and check out process left a bad taste in my mouth.