Update: Cissi has now move to 28 D'Arblay around the corner so I now go there.
And it's because of Cissi who works there. They lease out the chairs and I've heard all of them do a great job, but when you find someone who knows exactly what you want and what will look good on you, you don't go anywhere else. That's how Cissi is. And she won't cut or colour your hair if she won't think it'll look good. She's honest. She's good. And they serve wine/beer/coffee/etc and play good music.