The listed rates for the 11 pull is still the same as regular premium (0.5%/6%/30%/63.5%), though that's clearly wrong.
Got Greenbell with the single pull, 11 4*s with the second step, then Delphinium and Rabbitear Iris from the last two steps. With luck like mine, guaranteed 5*s are easily worth the 20 gems each :P
(also, I'm left with 499 gems after that; jeez, has it been so long since the last time there were any gem deals?)