I stayed two and a half weeks at Veruska's appartment which is really perfectly located - I was going to Kew Gardens, King's Cross and Hampstead Heath for running regularly and it's very well connected (2 minutes to the Underground and the Overground), nice cafés and restaurants nearby, also a smaller park for running, you can walk to the Barbican, wifi in the flat is fast and the flat is very bright. It's just outside the more busy area on Upper St., which I found particularly nice. Veruska was very quick to respond, very helpful and reliable. Would definitely go there again.