Despiste being very small it's a very functional house! It has everything you need to stay for a couple of days. It is also a confortable house, we felt good in it.
The only problems are the lack of an oven (if you plan to cook) and sometimes you can easily hear noise coming from the neighbours (if they or the TV is loud).
The best thing about the house has to be the location! I cant think of a better zone to be while in Madrid, you're near everything and it is in a very beautiful part of the city. You also have everything you need in a 2 minutes walking distancie (metro,supermarket,restaurants) - 10/10!!
The apartament was very clean when we arrive and the person that gave us the keys was very pleasent.
Overall it's a great choice if you plan to be in the center of Madrid and not waste a lot of money for it.