We stayed in the High Tech Avenida Gran Via, which was reasonably priced and very well located, both for the metro to the airport and for walking around central Madrid. I would not recommend it for any other reasons, as it was a bit grotty in the public areas, the central heating could only be melt-down or switched off, and the rooms have a bizarre glass-walled bathroom, so the only option for not witnessing sig other's morning dump is to go for a walk. If you choose to stay there don't bother with the breakfast - there are excellent cafes to be found across the road, if you turn left and downhill out of the hotel entrance.