Luckily I can confirm so many of the great opinions written before :)
The accommodation is clean, comfy and quiet (no noises from the pub) and really close to London's tourist center (10 min walk to London Eye, Big Ben and Houses of Parliament) as well as to Waterloo station (5 min walk). It is located in a nice neighborhood and there are supermarkets and nice restaurants close by.
I will definitely keep this place in mind for my next trip to London!