Darkside Tire Cupping?

On my 2008 SWING I have nearly 30,000 miles and am on my 3rd set of Pirelli Diablo tires.  My last tire has experienced severe cupping - not so on the others.  I am thinking of going darkside for my next rear tire.  Has anyone had cupping with a MC tire then did you get cupping when you went 'darkside'?  Has anyone had any cupping with a darkside tire?

Wow three sets of Pirellis and the set that came with the bike new? If so to me 30,000 miles is not many miles on four sets of tires. Heck even if you thru the OEM tires away when new, 30,000 miles on three sets is not to good to me.

Seem just about right. My rear tire never gives me more than 7,000 miles before I need to change them.