My data is starting to look like higher bet levels are dropping the payback on the main reels. Not enough spins to make that a firm position, but that's what I'm thinking at the moment.
I think it would be rare to find the lower denoms at a playable level, due to how the bonus works.
Also, there is usually a line. Crazy popular game.
I have to go watch some YouTube videos or something. I just don't want to believe the main reels are programed to hold 65% at max bet.