I use a Selle Italia Cycle Eyelink on my road bicycle.
http://www.amazon.com/Selle-Italia-E.../dp/B00CDPDIOA
I use 2 Zefal Dooback mirrors on my Trek Soho Fred bicycle
Amazon.com : Zefal Dooback Bicycle Mirror (Left) : Bike Mirrors : Sports & Outdoors
I feel much safer in traffic being able to see easily behind me. Helmet mirrors or road bike bar end mirrors are not that useful.