Custom Item Sets?

I dont see how to have your own custom item sets. I launched the old client to adjust item sets, and when I swapped back, the item sets were deleted when I created a custom game. I'd love that feature to remain, if at all possible. It helps me buy my mejais faster when I die and get a couple kills post death. >: )

I dont see a reason to remove that feature and I'd love to not have wasted my time setting it up for my champions that I play often. kappa