Hey Maybe they will improve your radio reception like those cell phone magnets.

LOL
Really though I've never had a problem on my models or heard anything bad about them from Helicopter, glider, and electric guys that has used them. I think gliders would be the first to complain because the magnets would be so close to the receivers in the cockpits.
Hmm this might make an interesting range check experiment. Range with magnets and without.