The Panic is the Messenger Pearl without a core, to be facetious. Its core has very low Rg differnetial, which translates to very low flare. So, the core's RG, plus the surface, plus the oil pattern, plus the bowler's speed determine the hook and length. The backend will NOT be affected by the flare, which means minimal backend. "Minimal" does not mean none! It just means lots less than the Messenger Ti Pearl, which has more than average flare potential.
The Fear is solid (as far as I know) SuperFlex, highly polished, with high RG for lots of relative length, plus VERY large RG differential, which translates in LOTS of potential backend.
Soooo, the Panic could be construed as a control ball, while the Fear is the opposite. Use the Panic if you need to clear choppy heads and yo uhave decent revs for decent backend. Use the Fear if the there is no carrydown; it should have a SIGNIFICANTLY larger backend than the Panic. Use the Fear if you lack "hand"; its huge RG differential should provide LOTS of backend, on short oil.
My 2 cents. FWIW.
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