The whitest one I've seen to date was a super butter (essentially the same as a super lesser imo), though lesser x mojave can also make pretty white ones as well. However, I wouldn't want to breed a BEL from 2 different alleles of the complex to any other member of the complex because you'll have a very hard time telling what exactly each BEL is. I would personally stick with a super lesser/butter and just look for the whitest one I could find.