Several months after the Ursines were introduced, I see very few of these on the battlefield, versus the tried and true Triton and Cu. I prefer the Triton over Cu, as it can have higher wrestling (130), as well as higher resist spells (~190), at no scroll cost, and mounts are NOT needed for 90%+ of boss content. So, the relative non-existence of these in real use is telling.
Don't forget the Triton/Cu/etc healing skill can also trigger and heal the player. Though it's not really reliable/controllable.
Life leech is sort of gimmicky. The only way to really rock heal from damage is using skeletal dragons (command undead)...
A mage using death ray or spells with the right slayer can out damage any single pet.
mage damage
Once you realize that a mage can out damage the pet, it's not really too important whether it has 700 STR, or other cookie cutter builds like the Chiv/AI build.