Sadly I don't think we will stay at this property again solely because the room had no ventilation and as a result we couldn't use the air conditioning.
When we arrived the rug under the air con was sopping wet, and during the night so much water dripped onto the sofa bed from the unit that it soaked through the duvet and woke us up. We asked for this to be fixed but were told that it was 'just condensation'. While this might have been true, it was an excessive amount of water so we could not use the aircon on the second night. This led to our room smelling musty and made it difficult to sleep on the second night even though the weather was relatively cool.
On the plus side, these suites are in a great location close to Atocha train station and the museum quarter. There are loads of great places to eat and drink nearby and the area felt safe. The rooms are attractively decorated and well equipped, with free tea and coffee and a fridge. The staff are friendly. They have convenient lockers for luggage storage, thought this would have been better if it had been available before check in as well as after check out.
In summary, then, we would have liked to come again, but because we always visit Madrid in summer I don't think we could take the risk of faulty air con again. In a city as hot as Madrid in August, a well ventilated room with working air con was really non-negotiable for us.