Considering the trouble to obtain other similar focus items in this level range, this item is fantastic. Sure, Skull of the Spire Servant is pet power 55, but its a random drop and its a single use clicky that only lasts 5 hours, if you even get lucky to get it to drop, and remember the cauldron is only available from another higher level mage who can conjure it every half hour. The other alternative would be Energized Wire Coil (pet power 45), which costs 747 Faycetum, farmed slowly by doing special missions inside The Mechamatic Guardian (good luck with that..).
In my humble opinion, this is the most convenient pet focus item to obtain while doing your missions for Paragon's Ear Stud of The Summoner (pet power 80), but then again, we're already wasting time by playing video games, right? so you may want them all. ;)