Deges,
I can't tell you if you have overlap or not; that really depends upon your style and how you have them drilled and prepped. Here is how that arsenal would work for me:
Heavy: ??
Med-heavy: Secret Agent
Medium (good midlane): Paradigm
Medium (backend snap): Domination
I haven't seen enough of the Shift to know exactly where it would fit. Now, like I said above, maybe you get enough variation to make all of the balls you listed work well within your arsenal. I just don't know.
Still, I think you probably have room for a lighter condition ball and one for truly heavy. Just my .02, but it really depends upon a lot of factors.
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I've only bowled 300, but I've benched 345
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