Just did lhr-cpt (747) and cpt-fra (340) in J. First experience on SA, and I must say - one of the best business class flights (both of them) I've experienced. I guess we got one of the 'good' crews. We were offered wine (too much of it), and the glasses were never, ever, empty - until we finally both passed out. Catering was well above my expectations. My only complaint? The older seats on the 747 were a bit tired. Apart from that - I really couldn't find a fault.
These were reward tickets, booked about 5 months ago.