I stayed with Elsa one night and she couldn't have been nicer. She gave me great directions to get from the airport to her home by bus and let me drop my luggage early in the day so I could see Madrid in my brief stopover.
The room is lovely and it's very close to the Metro so getting downtown was a breeze. She did everything she could to make me comfortable. She even offered to get up at 4:00 am to make me breakfast! The cabify back to the airport was only 10 euro. I'd highly recommend staying with her.