I've jumped on the bandwagon as well, purely after seeing this thread and booked us up. The saving is huge over normal cost, and I also managed to get Business class domestic flights and car hire included for the price quoted in the thread title.
My only slight concern is point 11 in the terms and conditions above which states payment must be made in full. I booked through BA Holidays like mmxbreaks, which allows just a deposit to be paid now and the balance at later date, should I be worried/pay in full now (I'd really rather not at the moment)?
This will be the first time in BA First for us both. I looked at outbound via JNB as suggested however the extra cost just wasn't justifiable