Staying so centrally means you can easily come and go if you don't want to eat out or you've forgotten something, and the Madrid public transport system is excellent and just about at the front door. N4 is generously stocked with the basics as well as suggestions for what to do, a map and books to point out places of interest and things to do. It's in the heart of places to eat, shop and sightsee and is within easy walking distance of the art museums and other places of interest. Unfortunately there was disruptive roadwork right outside the building during the week I was there. I was notified about it but didn't realise how it would affect my stay.