It really depends on the occassions you play, and your style. Me, I keep a rather huge mountain of balls with different drillings, coverstocks and surface preps - but I play a traveling league and visit about 5 very different houses for training every now and then, where I learned which material works well and which not.
Surface prep is the most important thing to influence ball reaction - so a purposeful prep and good maintenance (cleaning etc.) are important for a good performance.
Polished balls will have a rather sharp breakpoint and tend to be flippy, a sheen or even dull ball will rather arc and react softer, sometimes easier to control. A polished ball will also skid in oil and react when it hits dry ground, while a sanded ball will grip earlier. If you "mix" this with certain coverstock and core characteristics, you can make an educated guess how a ball will (relatively) react.
If a ball does not react to your liking, changing the surface is the best thing to do - and it is quickly done.
IMHO, having at least a small variety of coverstocks and matching preps is vital if you want to become competitive on a wider range of conditions. I'd go with a polished pearl reactive for lighter, fresh conditions, a polished or sheen light load particle ball for medium conditions and tough shots, and a sanded solid ball, either reactive or particle, for long and soupy patterns. The medium ball might even not be necessary at all, it really depends on how much you can adapt your game and how wide condition range of the lanes you want to play is.
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DizzyFugu - Reporting from Germany
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