I found this to be interesting. Sometime in the near future, Roto Grip is going to release the Defiant. Not only does it have an interesting core design- it's going to use a MicroBite cover which is very similar to the NRG cover on the Virtual Gravity Nano. All in all, it will be the strongest ball ever made by Roto Grip and very similar to the Nano.
Link: http://www.bowlersdeals.com/roto-grip-defiant-bowling-ball/
My arsenal
Heavy Oil: Storm Virtual Gravity Nano: 2000 AB
Medium-Heavy Oil: Storm Anarchy: 1500 polished
Medium-Heavy Oil: Ebonite Vital Energy: 4000 AB
Medium Oil: Roto Grip Nomad Dagger: 1500 polished
Medium-Light Oil: Roto Grip Rising Star: 1500 polished