We recently stayed at Studio 1 on 11 Gloucester St. and were satisfied by the cleanliness of the apartment, its size (other reviewers keep saying it is small but we found it totally in line with hotel rooms) and the amenities included.
In fact, we found nice smelling clean towels and hairdryer, soap, food for one breakfast (milk and cereal, hot chocolate) and pots and pans, even cool water in the fridge which was nice after traveling and arriving late in the evening.

The studio is in a very strategic area of Victoria, a few minutes walk to the underground and bus 24 a few metres away. We took that bus all the way up to Camden town and came across all main attractions in London, including Westminster and Trafalgar Square! It was a nice way to experience the city like a local without taking the tourist double decker bus.
Around the studio there are several shops and restaurants + bars, even a big supermarket where we bought some breakfast food when we didn't go to our favorite breakfast spot "Le Pain Quotidien" for a fresh bread basket with delicious jams :)

Unfortunately we had a few problems with temperature in the room. The bed is positioned right next to the window and the room is in the lower ground level and perhaps with the lower temperature and the winds there was air coming in through the glass panes. This was worsened by the fact that the heating system was not properly turned on and we were therefore unable to intervene. Alessandro fixed this for us and on the second night we were able to sleep, however there was still cold air penetrating from the window. That this was a temporary problem which I hope is no longer an issue now that it has been reported by us,

I would strongly suggest switching lamps in the studio or putting a smaller table light as both lamps provided were either white light or way too bright, this just made the room less "homey".

On a personal level, it wouldn't have been a problem to share the floor toilet -right next door- if it wasn't for the fact that the other couple next to us left it unclean (dirty toilet and hair + shampoo foam in the shower). It's just a matter of respect... well, this does not depend on Alessandro and we must say that every morning the bathrooms were cleaned by the staff.

To sum it up we would definitely consider staying at one of Alessandro's studios in the future, with the option of a private bathroom next time.