My personal comment is: *finally*, a familiar that is probably worth using!
Compared with Timber Wolf, which is generally agreed to be a very good creature: for +1 spellbook point (trained), a slightly worse but still respectable attack, Legendary, and +2 mana cost, we gain Channeling and useful-looking Familiar spellcasting. Different comparison: the glut of Unavoidable attacks in the game make this Familiar much, much better than say Fellella, for the same cost.
I would have to see it in play before I passed final judgment, but...it will definitely see play.