to me it depends on if you are wanting a practice ball or pitching balls. I did get a dozen of the Mach 1's from WarriorMike a while back and have had great luck with them lasting for practice. I also have a mixed bucket of Thunder Heat's and Dreamseams for the pitchers to pick from.
Dudley Thunderheats ASA slightly outlast the Dream Seams when used for team practices, team hitting and the numerous hitting and catching lessons I give. That said, it's not by very much. If you're going to use them for pitching also, go with Dudley's or Dream Seams because they have the best seams for pitchers IMO. If not, Include Sterling and Diamond in that group. All are quality balls that will last.
+1 On the Sterling... Over the years we have tried just about any and every brand out there. DD is a pitcher and prefers the "tackiness" of the Sterling cover.