It really depends on the surface, distance, volume and type of machine applying the oil. In general, you should choose more rolly control balls over skid flip monsters.
If you can go with three for the whole season you are better than me. I didn't really become a ball ho until I started Sport Bowling four years ago. On the China, many of your balls will give you a similar reaction. On a Sport Condition, the true characteristics of your ball will become much more evident.
Good Luck!
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got revs?