We stayed at Sylviane's place for 2.5 months over winter while we were in between flats.
Sylviane's place comes fully equipped for long stays, with lots of kitchenware, linens, and a warm and bright bedroom. She has a LOT of unique decorations in her flat. Whether you like this or not depends on your taste, but it's certainly interesting to look at. There's not a huge amount of space if you bring your own gear, so if like us you had some furniture you'll have to manage space carefully.
The location is fantastic. It's a very short walk to the canal, Shoreditch, Brick Lane and Islington. I rode Santander bikes to Covent Garden every day and it took about 30 mins. It's also right next to Shoreditch Park which will be amazing in Spring and Summer.
Sylviane was overseas during our stay so on a few occasions when we wanted to ask questions it took some time. However she was responsive and helpful and I'm sure if she's nearby there'll be no issues. The building is a bit old and quirky, so there are some rules you'll need to follow, which Sylviane lays out in a welcome pack.