The math argues from a perspective of 30-man hordes, which is very uncompetitive for an 'always-strike-last' unit with toughness 3 and an 'okay' weaponskill.
Sometimes a post is so rotten I have to respond like dr.Cox -- My Dwarven painting log -- My Lizardmen painting log -- My Scurrying Skaven painting log -- My nurgle beastmen painting log --My Tau cadre painting log -- My knights of the white wolf -- My Ork painting log
---> Newest: 13-5-2013; Lizardmen, tournament pictures, Won best painted army! ---> New: 7-4-2013; The friendly riptide saves a firewarrior
I think 1 of each is the right answer. If you consider 20 pts from each being a power/dispel die, and let's say 60 pts being the S5/T5 chariot you get from the deal (worth more than that in reality), and the luminark providing protection to the hurricanum, then the bound spells and buffs are incredibly cheap for what you get.