I can't compare to other London hotels, but I can certainly say that the Ridgemount was a good choice and I'd happily stay there again. The decor is home, not hotel, the staff were so helpful and nice, including and especially the owner - not in your face helpful, just very accommodating, always there with an answer or help. Though there was a group of students there our second night, the walls must be thick because we couldn't hear anything from any other rooms! The free breakfast is a great start to the day, served by friendly staff again in a clean, pleasant room downstairs. The room was actually larger than I expected - we had 3 singles and a double and I expected them to be much tighter to each other than they were, there was plenty of space for us. Location wise, when we got there we dipped out to the British Museum for the afternoon which is practically on the doorstep, there's grocery shopping round the corner and plenty of restaurants on Tottenham Court Road parallel (highly recommend Franco Manca if you're in the mood for pizza, inexpensive and quality!) It's not far from a couple of tube stations and a couple of the open top bus tours, and within walking distance of Kings Cross station.
The shared bathroom is a downside of course and something to bear in mind. Only rarely were all the bathrooms occupied (be aware there's another shower and toilet on the top floor), it's not ideal but in in an old house in London there are limitations. But they were clean.