c-parekh2317530 wrote a review of Smith Interlock Prophet Sunglasses - Polarized on November 10, 2009
I use these for multi-day backpacking trips. The reasons are 1) they are sturdy 2) they grip well with sweat and rain 3) they provide enough wrap that I can look all the way up/down and right/left and my eyes are protected, and 4) I like they way the look and feel.
Perhaps the only drawback is that since they wrap a bit, they don't fold flat. This means that when you store them in your pack they take up a bit more room than non-wrap glasses. Of course, they provide a lot more sun, rain, and wind protection. Especially in the snow.
I would like to see them sold with a poly chromatic lens. the Polar Gray and Ignitor lenses they come with are great for bright and medium/low light, respectively, but a poly chromatic lens would work in all light conditions without needing to switch.
Switching lenses is easy, but it does require you to stop, open your pack, and stow the old lenses if you want to do so.