The location is absolutely terrific and the flat is very nice and of a more than decent size for the standards of central London. The kitchen is also spacious. The bathroom is petite but comfortable. No problems with the flat then, but it's the whole building to be too old. The stairs creek loudly and they are dark with funny, flashy lights which take ages to be fully on; these things, of course, have nothing to do with Marek's flat and they are quite common in London.
It is no mystery that the place gets noisy in the weekend, but nothing too unbearable really. In fact, I have spent a whole week at Marek's place with my parents, who are not exactly the travellers type: if they haven't complained, it means there is no real reason to complain.
Finally, Marek has been very helpful and our communication has been clear and prompt all the time.