Roto has, in my honest opinion, the widest selection of stuff out there right now, and all of it is excellent. If you look at, say, Ebonite or Hammer, they have tons of stuff that does pretty well on medium-heavy conditions -- i.e. Angular One, Black Widow, Total NV, Toxic, Pain, The One, etc. Roto, on the other hand, has your whole arsenal covered, and everything has its own little niche. Every piece has a spot, and functions in that spot. You just can't go wrong with a Roto.
Don't forget the Saturn and the Venus too...or the Battle...or the Odyssey...or your good ole' SureDee Seventy Three Classic...
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I am the University of Virginia's Bowling Team. After all, one All-American is all you need.