Seb and Sandra are great hosts. The apartment was always clean and tidy, the room is very cozy. We didn't see them often as they had to work, but they were always around when we needed some information or had any questions. The area was quiet and safe, still you could get to London City quite easy. It takes about 10 to 15 minutes to get to a overground or underground station, but you should be aware of peak times (at least if you don't like to cuddle with strangers.. ;-) )
It is close to the Olympic Park with little canals which is also nice to visit.
We enjoyed every minute we spent with Seb and Sandra and their dog Leia is very cute. She might sneak in if the door is not closed properly, so you should be aware of that :-) But it was no problem at all, she just wants to play and cuddle.
If you plan to visit London, we highly recommend Seb and Sandra and their accommodation!