I really like the Take-a-Look mirror. I wear glasses and have angled it upwards a few degrees and keep it positioned in the L shape from my ear out to just above my shoulder. Five years now with the same mirror. It's really nice to find a product that does what it's supposed to do and is reasonably priced.
http://www.coloradocyclist.com/product/item/BPPYLZJ7

Roy Curry
Hixson, TN