I've been wearing Smith sunglasses for about 10 years and have become very fond of my Threshold "Sliders" which have three sets of lens (dark, light, clear). They block the wind well, the lens interchange is easy and super convenient. I was also happy they have metal spring temples, so they can be bent to fit not just plastic that doesn't retain the shape.
They're not cheap, but Smith has always replaced any broken pair without question under their Lifetime Warranty. (I've broken two pair so far in 10 years)
http://www.smithoptics.com/Threshold-Slider_30_31.html
