I've got a tropical storm with a Rico drill which goes really nicely on short/dry patterns, pin's around 5" from PAP. Really nice shape to it, although with my high track it bumps the fingers a little just before it hits the pins sometimes, but I don't worry about that.
From what I've heard the CV is a decent choice, although I've also heard that it's stronger than advertised... Hammer seem to have a knack for doing this... So if I were you I'd err on the weaker side with the drilling, 5.5" pin maybe, I think Rico would work well, or a high pin, 1.5" or more about the fingerholes.
Other balls to consider, if you're not wedded to the hammer idea, are the legends straight flush, track desert heat (if you can find one) ebonite tornado, or a good old urethane if you can dig one up, I've got a black U-dot which works a treat!
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Reporting from England