The flat is in the best position ever, with one minute walking distance from the metro "Tribunal" (which links near to everything in the city) and next to Malasaña area.
The room has a great window with a small balcony that provides quite an amount of light and air, on the side of the main street. Because of that sometimes it can be noisy, but it's in a very central area so we didn't expect anything else really. Also, bed and pillows were comfortable.
Bathroom is in common with the other guests, it's quite small and it has no windows. That was really the only not so good thing about our stay: sometimes we found it a mess, and quite smelly too. Also, the shower was not very comfortable in my opinion.
Communication with Diogo was good, he was ready to answer in few minutes. We had some troubles with check in modalities, but he helped us very quickly.
In the end, we recommend it!