peter d said:The breakers are inferior.
I briefly worked for an electrical supplier that was a major GE distributor. We would constantly get returns on breakers that were junk right out of the box (mostly the handles being stuck open, closed, or middle position). And those were the ones that guys actually returned. Many of them told us that they just threw the junk ones away.
Every manufacturer has that problem. It's a result of mass-production.