Our stay at Simon's house was simply great.
The place has a very nice African feel with its big windows that let in a lot of light, something you cannot get tired of in South Africa. There's a little patio in the back and a little garden in the front with the swimming pool when you can't handle it anymore. It's located in Observatory which is not really in the Centre but has it's own little hub of nice bars and breakfast spots on Lower Main. Very close to M5, M3 and other main roads that will take you everywhere in the city. If you don't have a car grab a bus taxi 100 meters from the doorsteps.
Simon was very friendly and helpful with a lot of tips about the weather (we came there to surf/ kite surf) and Western Cape attractions in general. He's a musician spending his days writing new songs upstairs so if you need privacy he will definitely not stand in your way. But if you want you can convince him to play some Bob Dylan for you ;) He basically let us use his whole house and made us feel at home.
We wanted to stay for three nights to look around but we ended up staying for another seven before we moved on to Muizenberg to catch some waves.