if it's done the same way as other presales: the allocation for the Visa presale won't be the same as the allocation for the fanclub presale;
and which (if either) will be better is anybody's guess.
i know it's real hard in this situation, but for what it's worth, the best thing i learned from watching the presales so far has been:
don't panic: ie, don't buy tickets you aren't happy with - and then be happy with the tickets you buy.
"What do you want - what?!"
- Keith