I don't have the money, but if I did I'd buy glasses that have the aviation style ear ends.
I have to take off my glasses to put on or take off my helmet, and with the normal style glasses this is a pain. Not only that, but the anti-fog setup on my HJC FS-10 helmet works great for the shield, but my glasses fog up pretty good. So, I was actually thinking about contacts. "Which way do I go?"