I've run into a similar case where our shot is different each week on AMF SPL. Typically I will have 5 balls with me on league nights as I usually keep 2 stored in the lockers and bring 3. I have Defiant when I run into heavier volume, Critical Theory, Outlaw, Nomad Dagger and Frantic.
Being right handed, one way for me to tell is when you start leaving flat 8-10 splits, flat 10's, when you start going through the beak even with multiple lines, or if the ball starts to puke in the backend resulting in loss of reaction. Usually I can only go 1 or up to 1-1/2 games with the Defiant before I have to switch.
So if you decide to go with the Virtual Gravity and go down to the Cell Pearl, keep an eye on reaction and your carry. When carry starts to suffer with the Virtual Gravity, the ball is telling you that you'll either have to make an adjustment or make the ball change.