I tend to think that you get the best value and quality with a sunglass house/maker than a designer brand. Brands like Maui Jim, Ray Ban, Oakley, etc have reputations to live up to and tend to have good optics. Something like Gucci, Armani, etc are going to be the exact same manufacture or worse and cost twice as much due to the little logo.
I personally would only get sunglasses from a specialized sunglass maker. It just feels like designers have no business with glasses
. Unfortunately I have noticed a decline in Ray Ban quality since they changed ownership. The old quality predator style glasses have actual glass lenses and a heavy duty frame. The new ones are plastic lenses and a much lighter and flimsier frame