Slower than Utrip, but somewhere around 300 cuts it gets really going.
I broke the GFs one in (well it was mine and she took ownership off me of it LOL).
I would take tee cuts and BP with a mix of 52, 44 and 40 balls at first. Wasn't too worried about barrel durability with the Disc.
Once the barrel was broken in, it mashed the 52 balls which as a Dual stamp is its job. It reaches a point where it is just an optimal option with the right amount of barrel flex without it getting too soft for the softer balls. The 52s need a barrel that is not too soft, and not too stiff to really make the ball compress and rocket off the bat and fly. Whereas the harder balls benefit from softer barrels creating trampoline effect.
In basic terms you need somewhat of a combination of Hard vs Soft to make it fly. Soft vs Soft is not optimal. With the 52 cor ball, the barrel is the "hard" required to a certain extent to get a piece of it and make it go. Whereas with harder balls, the "hard" is the ball and the soft is the barrel of the well worked in Utrip models.
Ever notice with 52 Cor the Miken 2pc (Freaks, DC etc) stuff hit really really well the first 500 cuts, but as the bat gets worked in and almost fails or does fail comp testing it no longer crushes the 52 cor balls the same as when it was new? But absolutely destroys harder balls now? Or the same scenario with the Combat Assault G4 2pc bats? That's the madness.
Because I hit a lot of 52 cor, I try not to BP my bats that are Utrip only with harder balls much. To keep them primed and perfect.
I hope to do the same with the Super Z Dual stamp model from last year, trying to find one cheap and get it broken in.
My gripe with the 4000 was the flex, too bendy.
The Super Z was perfect.
Dual stamp crushes the 52 Cor balls once well broken in and done so with a nice mix of balls to really get the barrel worked in.
Utrip breaks in quick, but if you keep hitting harder balls often, will eventually get too soft in the barrel. Which isn't ideal for 52 cor balls, but will hit the harder ones real well. And then eventually also fail compression testing. Whereas Dual has a longer life span with the Disc doing its job.
i have heard mixed reviews on this bat did the z4000 dual just start slow? how many hits till it opens up? I just bought one for real cheap with a return so i cant complain