In trying to answer your initial question between power-groove and tropical storm, I think it is a no-brainer. The Power-groove, just by the nature of its name, is no weak ball! It is a lot stronger than most people think. I know of one individual in my Monday Nite league that used it on mediums all year!
The Tropical is a strong ball as well.....it carries very well.....but is a much better dry lane ball than the PG. It also can be used on some medium conditions, dependent on bowler style and speed.
The XXXL is an excellent choice for a dry lane piece. Please remember though....everyone has a different idea of what is dry, however! XXXL's may be a little hard to find, however.
In my personal arsenal, the Roto-Grip Mercury, and the Hornet are both excellent choices for hit and carry, and control on true dry lanes.
Either way, you can't go wrong.
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