In reply to elliot.baker:
The sunglasses market is dominated by Luxottica. Their brands include most of the fashion brands (Armani, D&G, Burberry, Prada, Chanel and dozens more). Their brands with a lesser link to fashion include Oakley, Persol and Ray-ban. They own a number of retailers too, including Sunglasses Hut and David Clulow.
It doesn't mean that their glasses are any the worse for it - but just so that you know.
If you want really first rate sunglasses - Maui Jim.
Personally, I have issues with gloves, bicycles and sunglasses - far too many of them. I am always pleased with myself when I get past duty free without another pair of sunnies. It was a near-run thing a month ago with a fine pair of Maui Jims.