I've got a small one. I think it's around 50 pound pull or so. Probably too small and weak for fishing, but it comes in handy when working on a car in the yard and dropping small nuts and bolts in the grass.That's the same one I was talking about. Although I had no idea it was rated that strong. I think ideally you want a strong magnet but no so strong you can't get it free from any I beams or bridge supports if it sticks to them.
It's crazy how you can drop something right at your feet and it just disappears. LOL