As I got sick before the trip, my friend went on her own, and she was more then happy with the apartment. I definitely want to go there next time I'm in London.
Her words:
The apartment was perfect. Just 2 minutes from the next tube station, with everything really close by. The flat was very clean, and provided anything you need including a kitchen, and even an iron an ironing board. Also the interior design was really nice. The key exchange was being handled really easily, also Phil, the building manager was always easy to reach for further inquiries.