Storm has the Natural and the Natural Pearl, to cover that reaction shape. I am not speaking for Storm, but my .02 says that the Reactor cover, will just be more predictable than the Curelyon or pro glide cover. The oils being used today, move around the lane, and change differently than the oils that were used when those covers were out. I still have a Charge, and a Hot Rod (an NIB that I found on ebay, so it only has 2 games on it) with the old Curelyon cover, and it is very sensitive to the oil line, even on burnt up lanes. The Reactor is much more predictable.