There is plenty of bike specific eye protection out there, not sure why people are saying the M Frame is discontinued, as it is still avaliable on the Oakley website.

For Oakley value, not sure what the warranty is like in the US, but in the UK it's the best of any bike or bike related manufacture. Have had several pairs replaced when they were 10+ years old for a nominal sum. Yes you pay a premium up front, but unlike anyone else, they stand by their product.