Both bulls have their place. ACE OF DIAMONDS will NOT downsize,period. In fact he WILL work just the opposite.From my experience, Kool tends to breed big on big and small on small. Both are good bulls and Ace is bred to heifers with NO problems,by the folks that bred him. Ace works great on any of the Double Stuff lines,Sonny daughters,and according to friends in Oklahoma, he works well with some of the older shorthorn clubbie blood really well.