From what I've experienced so far, the Ultra Zone is less than the Fury Pearl but more than the Twisted. The cover of the Ultra is a hybrid (pearl/solid) version of the EnMotion cover used on the Twisted, so it does not seem as strong off of the friction as with the Octane cover of the Fury Pearl, but the core (modified Phantom used in the Blast Zone) makes it a little rollier in oil than the Twisted. Still not considered a heavy oil ball, but with surface adjustments towards 2000 or 1000, the Ultra handles oil well, just not the strongest.
RoB LaW
--------------------
I'm gettin' old, I'm hurtin', but I've got Brunswick balls.......Color me competitive.