Been there, done that. Actually, it was the biggest anticlimatic thing I did in Britain. Spend a hour and a half travelling by bus, tube, and walking to get there... It was a Saturday afternoon and the gf and I were the only ones there. The studio building looks like any other building and is closed to the public and is fenced off. There's a wall loaded with graffiti. And there's the crossing as seen on the Abbey Road album cover. That's it.