We stayed 8 days in Peter's apartment. The location was wonderful, at only 50 meters from Mornington Crescent underground station, from there you can go anyway in London in a few minutes. It has many markets around (restaurants, supermarkets, etc). It's a nice neighborhood, confortable, not noisy and it felts secure.
The apartment is fully equiped, so if you want, you can make dinners and breakfasts without problem.
The only (very little) things to say are that the stairs has no good light and no railing (so be careful), and the other one is that shower has a "trick": if you don't fully open the hot water faucet (and then mix with cold), you could suddenly run out of water in the middle of your shower and have to wait some minutes for it to start working again.
Overall: it's a great choice to stay, and has an excelent cost/benefit relation.