I tried both eye glass and helmet mount mirrors and just couldn't get them adjusted to where I could see clearly with my bifocals. I have a road bike mirror that mounts under my STI shifter hood. Not exactly a fashion statement for road bikes, but it does the job.
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HCFR Cycling Team
Ride Safe ... Ride Hard ... Ride Daily
2017 Colnago C-RS
2012 Colnago Ace
2010 Giant Cypress