Rare earth magnets are fabulous - and as long as you keep them on the edges you’ll do fine 
If you ever want to use them in the middle, keep in mind that in the 
at least, when the fan goes over them it often slows down and stops your work with a warning that your fan has an issue.
The solution to that is putting a piece of metal over the tops of the magnets, so they’re shielded and the magnetism can only go in one direction Harddrive magnets come with shields already attached so I’ve taken to using those.