I've got a Gravity Shift for quite a while now, and I must say it has a whole boat-load of games on it and the only thing I've ever had to do was give it some fresh surface then shine it up again. Takes well to surface changes, and the thing still hits like none-other. In fact, I've loved the balls motion and lack of death by getting another G. Shift before they got discontinued.
Compared to an R2S cover, the R2X is stronger in the mid-lane. It reads the lane earlier and has the same continuation. It honestly reminds me a lot of the Paradigm and Paradigm Passion bowling balls in terms of serious mid-lane read but backend reaction.
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Proud Supporter of Rob Stone
Obviously, you aren't a golfer.
Some stayed in the foothills, some washed logs like teeth.