We really enjoyed staying in London and Margaret's place was very convenient. She is a very kind and responsive host. It's a great place to stay the night but it's nothing extravagant. The furniture is very ikea and the place is a bit on the older side but it's perfect if you're not planning to spend too much time in the apartment (who would in London). :)
It's really close to the tube (can virtually get anywhere in a matter of minutes) and many really great restaurants.
Overall, I would recommend staying at Margarets!