I loved my blue pearl avalanche. I drilled it aggressive and it rolls great.(leverage pattern, big weight hole in the P3 quad) Which is why I recently got a 2nd for when the first one gets worn out.
I will say that I'm glad I drilled it aggressive, because other wise I could see it being a bit on the over under side.
I also did the same for my powergroove I recently drilled up. 3.75" x 4" with large P4 quad weight hole. Ball still clears the heads good but gets into a very strong roll with good continuation on the backends.
When bowlingball.com cleared out the grooves for $27 with free shipping I almost bought a 2nd just to try something different with later. If your a higher rev player then adding a powergroove or slingshot would work well below the slide.
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