I am looking for the best LED Lighted Magnifier for my grandpa. Any opinions?

It's been a while so I don't know the newer technology but I would suggest that rather than spending money willy nilly you get a low vision assessment from a qualified optometrist or optician who can make recommendations that are matched to his needs. (4X magnification would never have been enough for my mother, even in the earliest stages)

Look for UltraOptix 4X aspheric LED lighted. It is the only one I have found but I know there are others out there.