I'm just starting to replace some of my equipment with Roto Grip.  I started by picking up a light oil ball (Sonic Boom), because that's my most commonly faced condition.

Right now, I'm carrying the following:

Brunswick Strike Zone
Brunswick Zone Classic
Roto Grip Sonic Boom

I'm going to sell the ZC because I just can't match up with it.  What do you think would fit well above the Sonic Boom?  Probably a medium-heavier medium type of piece.  I was thinking about picking up an RSP for that slot.

As far as totally replacing the ZC, you might look into a Horizon pearl.  It's basically got the same versatility, but with a bit of a different look.

As far as the RS-P, that'd fit exactly where Shelley said - right between the ZC and the SZ.  There wouldn't be too much missing, again, since the Sonic Boom is moderately strong for a light oil ball.

As far as replacing the SZ, go for a Battle or the new Odyssey, depending on the look you want.  Same cores, different covers.
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