I wear progressive lenses in my regular glasses and bifocals in my sports/cycling glasses. I also use a helmet mounted or glasses attached mirror for every ride. No issues whatsoever and the quick check to the rear with helmet or glasses mirror, IMO, is safer then using a bar mounted mirror. Best of luck and I applaud your decision to use a mirror.
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Bob
Enjoying the GA coast all year long!
Thanks for visiting my website:
www.freewheelspa.com