Overall, this apartment is in a great central location and is extremely walkable to many attractions, bars/restaurants, museums, etc. in Madrid. We were able to comfortably walk to all of our desired destinations during our stay. The representative that we worked with was also very friendly, accommodating, and responded promptly to our messages.
Our main issue with this unit was the smell and cleanliness. The apartment has a noticeable scent of smoke and the bed linens did not seem thoroughly clean. It's also worth noting that the shower will leak onto the bathroom floor if the shower head is not significantly angled towards the wall. We needed to plug the shower door with an extra towel to avoid large water puddles.
If an excellent location and friendly customer service are your main focus, this apartment is a good choice!