I personally believe that your eyes are too valuable to wear cheap sunglasses.
Costas are a great value.
If you want a bargain you can buy them at El Capitan for $99.
Costas are very sturdy and will last a very long time if cared for.
I left my glasses behind once and bought some cheepies at a pharmacy in the keys. Honestly i could not wear them the distortion was so bad.
I find a good pair of polarized glasses are essential on the water.
There are certain things in life that are worth the extra change: Good food, Good glasses, good shoes, Bad girls, and my personal favorite good tackle. Or is my favorite Bad girls?