Very centrally located, and all the amenities you would get in a hotel. 5 minute walk to two underground stations and 10-15 minutes to Plaza Mayor.
There are a couple of restaurants downstairs that can give off some noise later at night, but they close around midnight. The electricity in the unit does go out periodically, but comes back in when you flip the breaker outside the unit.
All in all, great place for the price in central Madrid