Potato preferences?

Hi

I've got 3 potato grow bags plus 3 large tubs that I have used for growing spuds in.  I'm thinking of trying a different variety in each bag / tub so that I can have continuous spuds throughout the year.  What do you all recommend?  Also, how many in each do you think?  I thought about 3 or 4 max.  I'm going to buy seed potatoes from Ryton Organic as they are pretty local to me and I can buy individual seed potatoes instead of 1kg bags of each type.

OG