A fantastic apartment - clean, great amenities (it even has a washing machine, should you need it), but the best bit has to be the location; it's right in the centre of Madrid, within walking distance to absolutely everything, yet because it's in a secluded block it's quiet and peaceful - we didn't hear a sound at night. It's gated too - open in the daytime but closed at night, so very secure.
Ana was very friendly, and gave us and recommendations and tips at check-in.
I recommend this apartment whole heartedly.