I had a great stay. The studio flat is very modern, clean and has everything you need. Perfect for a single traveller or a couple. Cozy bed (1,40m or 1,50m), very nice bathroom, functioning kitchen etc. Everything feels new, which makes it very comfortable. Many places in spain have a bit of a "run-down" feeling, not this one.
The location could not be better. You are in the heart of the old town.
If I had to nit-pick, the oven did not work and you could sometimes hear the neighbors at night, as you sleep next to an inside courtyard that is quite echo-y.
Definitely 5 stars, though! :)