Hi there, I'm the rule nut Kereo mentioned (I prefer the term power gamer).

My main problem with sponsored magic is the lack of power/control bonuses trough specializations and focus items, as well as the lack of enchanted item slots.

To illustrate my point: All hellfire does is give you one measly point of power/control when at the same refresh cost you could take evocation + refinement, resulting in up to 5 extra points of power/control.

Keep in mind though, this is coming from a combat oriented player so not much regard was given to taumaturgy.