Use to be a member of the Storm Nation, but now I am 100% Motiv. I match up to most of their balls. The covers absorb very little if any oil, they take cover changes well, the cores/covers are usually well matched, and they rarely ever crack (exception the Tag, but I never owned one).
I have reported in past posts how many Storm/Roto and 900 Global balls I have lost to total cracking.