Bumping this old thread for others since there is almost no documentation on IO STORE
For me this saved my game. I am porting my game to the Xbox Series X (4.27plus) and I was getting terrible texture lag and frame time jumps.
Packaged with IO STORE and my game runs perfectly smooth! So all I can add is if you are packaging for the Series X turn IO STORE on (and Create compressed cooked packages)
I believe it also has to have Oodle plugin on (which is installed and on by default in 427)