Storm's coverstock durability has been pretty good for me.  The new R2X coverstock (so far only on the Dimension and Gravity Shift) is supposed to be a longer life cover as well.

You said you're looking to make a change, right?  Maybe try a little rollier ball and put a long & strong layout on it.  Maybe a Dimension if you want to try a solid, or a Gravity Shift if you want to try a pearl.  Looking at your profile, your game sounds very similar to mine.  I personally love my Dimension, it's my go-to ball on almost any condition from medium on up.  I also have a Gravity Shift, but it's got countless games on it since I bought it used for a friend for dirt cheap.  I need to extract some oil from it to find its true potential (and even then it still hooks a ton when it finds some friction!)

Well, talking skid/flip reaction wise with Storm's current lineup, you cant not look at the Rapid Fire Solid and Pearl... The Twin-V is one of Storm's best cores ever put into a ball. Those 2 will give you a skid/flip reaction, but wont be able to handle as much oil as the Widows.

All of the balls in the Shift line, if drilled correctly can have alot of backend movement and with the Shift series, you get the Solid(Attitude Shift), Pearl(Gravity Shift), Particle Pearl(Shift)

For your questions:

1. Ive never had problems with coverstocks on any of my balls, including Storm and Ebo, but I clean and resurface regulaarly
2. Twin-V and the Shape Lock (HD) to me are the most skid/flip in Storm's lineup.
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