As far as i can tell this is a total piece of crap. The only thing it was useful for is finally confirming there is a 50% reward enhancement cap.
It gives around a 2% reward increase. Wich isnt enuf to replace any of the other reward % pieces, and isnt even stronger than +2 mind from a cheap star earring. It does not increase the regen duration or reduce the timer.
It might increase the regen potency but i have no easy way to test that.
Basically this is a +3 pet acc earring, ignore the enhance reward.. it lies.
and in my opinion +3 pet acc isnt worth an inventory slot.