How are long pimples unpredictable?

Hi

My friend wants to get a bat with long pimples or anti spin. I have heard that long pimples are unpredictable, but how?

I was also wondering what are the advantages of both types of rubber?

Thanks

Hi Sam,

Long Pimples are not unpredictable but they react in a different way to inverted pimples.  This is why they may feel like they are unpredictable.  They are more difficult to control than anti spin but the effect of the rubber isn't as much with the anti spin.