I don't know anything further, lowrez, although she just won the NDW 100 in a course record time and her blog didn't mention anything about blistered feet, so hopefully the whole heap of concoctions has done the trick.
Same shoes for me as I would use for a road marathon, same as lowrez. Mine are Brooks Adrenaline. It's worth going a size bigger. This year I forgot this and wore my usual size and suffered the only blister I have ever had during Comrades, as my toes got bashed on the downhills.
lowrez - A while back Debbie Martin Consani wrote a blog about how she had solved a recurring blister problem. Quite complicated but it might be worth bearing in mind if you do a long ultra again. http://debsonrunning.blogspot.co.uk/2013/03/best-foot-going-forward.html
It's funny that the advice is no more than 50km to 55km but that's what I am going to follow this year. In previous years I've done 40m, 50m, 55m and 45 mile races prior to Comrades but, in hindsight, I'm not sure that any benefit from them is going to be outweighed by impact on the body and recovery time. I figured that, as I don't do more than 22 or 23 miles in training for a marathon, as the benefit of such runs is outweighed by impact on the body, this made sense. We shall see.