Right, so I find that with proper magnets I have yet to find 1/8" I can’t unwarp. I stack 2 magnets on each other, and they just yank it down. Hang on, I’ll go get a picture of my magnet rigs, I already stack 2 magnets in each unit.
Here we go:
I tape my magnets up to protect them and make them easier to pick up, and find that the discs are ridiculously strong. The bars are nice and narrow for laying right along the edge. The discs, being really thin, can be stacked with another pair so that you get 4 stacked on top of your piece. It’s really very strong.
Ymmv, but so far, so good!