I very rarely see nickel cases flake or chip the coating off. I use quite a few nickel cases in pistol and rifle and the nickel does wear through over time and the brass starts to peek through. It's an abrasion though, not a flaking usually. It looks the same as when you gradually sand through paint to reveal the substrate.
The only nickel cases I've seen flake were quite old; decades old.
I try to avoid saying "plated" because there was an official statement from one of the big US ammo manufacturers, I forget which, who said the industry standard is no longer to use nickel plating but a different chemical transfer system (trade secret and every manufacturer varies it slightly). Apparently it avoids all the flaking problems. Whatever process it is it does seem to increase brittleness in the cases so they do tend to split sooner.
I've sized many nickel cases and never damaged a die; carbide or steel. The only dies I've lost to damage were because of sand and grit getting stuck to the lubed cases when I used to use spray lubes. I didn't notice some dirt in the bottom of the box I sprayed in and it stuck to the lubed cases.
Nearly all the nickel cases I use that I don't have a problem with are Federal. Don't know if that makes a difference. I think most of the old cases with flaking/chipping nickel I've seen are Winchester but I've got a good number of recent Winchester nickel cases and they seem to hold up well.