I assume you're talking about the Buckblaster? I think I recall on Rocket's site that they developed this one for people with high ke setups that were blowing through deer and wanted to slow penetration down a bit so their arrow didn't travel so far out the other side of the deer.

Game tracker has one out that is also a hybrid, it has a fixed two blade main blade, and two blades that swing out upon entry that enhance the blood trail. I think their design wouldn't require as much ke to provide good penetration, but they both seem like overkill to me.

I'm starting to think that if the head is quality and your bow is well tuned and over 60 # of ke or so, shoot whatever head flies best for you and looks the coolest