Private Pilot magazine from Sep 2003 did an independant study to find the best sunglasses based on various tests showing prismatic power, refractive power, definition etc. Oakleys came out well in front, Serengeti were 7th.
I can't remember the web link but I do have a copy of the .pdf file if anyone can make sense of it. It's light reading for an optician but mostly gibberish to me
