Serengetis----->AMEN
Flew the bus for 6 years..Also fly mil for 20+ years. Went through so many sunglasses. Best sunglass for me in any flying /driving environment are Serengetis. They provide a tint and clarity that is unmatched in anything else I have used (Ray-Ban, Oakley, Arnette, Maui Jim, etc). They sell them in CA at the Big 5 Sporting goods stores...have sales on them every few months or so - sometime down to $40 - you can try them on there. Like them so much, I bought 5 of the same pair. I am religious about keeping them protected and scratch-free. I have the Cascades FWIW.