What Phantom said!
Bensen's machines were not nearly as stable or safe as Bensen could very easily have made them. Given that Bensen marketed the B-8M gyro as something of a consumer product, along with that went a duty, IMHO, to make them more beginner-friendly -- but Igor refused to do so. We're still living with both that attitude and the "widowmaker" reputation it has earned our aircraft.
That said, the advent of the redrive with long prop made things worse. The redrive is a torque multiplier, worsening the torque-over problem. The long prop with Bensen's seat location creates a large CG-thrustline discrepancy, worsening the PPO problem unless a powerful H-stab is added.
The KB-3 is no more to blame than any other gyro of its era. It's typical of the gyro designs released in the early years of redrive engines, especially the Rotax and Subaru. First-generation Air Commands and RAF-2000's, as well as the KB-3, were afflicted.
It took a couple decades, much prodding, a whole lot of nasty bluster and B.S., to get gyro builders to address the issues. In fact, the battle isn't over yet, though things much better than they were.