I completely agree about reliability. I've done a decent amount of testing, and I'm confident that I've got a reliable G20 hardcast load. But I sure wouldn't carry anything that I hadn't personally tested.
What happened in your .40? Was it bullet profile or ?
My plan is not to shoot at a bear at all, but if that fails, I know I'll be aiming hard at the brain. But would you say that it is a lower but reasonable probability that a heavy wide meplat handgun bullet (.44 or 10mm) strike to the shoulder could slow/stop a bear? That's really the only reason I can see to carry anything other than a 9mm with Lehigh.
Another question: do you carry your bear defense load when you return to civilization, or do you swap in a more conventional defense load?