I wear a Pair of Oakley Metal frames with prescription lenses. They are curved to keep the wind off my eyes and give great protection from the sun. They also fit tight to my head and stay put.

The cheap option that you can afford to lose is the tinted frameless safety glasses you can buy at any big box store. They stick tight to your face with no eye watering. I used to carry extras in my cat for the passengers. Wear them on my bike all the time as well. When you get to where you are going break out the cool Oakleys.

Polarized are great unless you have a digital dash or need to see the GPS.

I use the Oakley split jacket with the wind gasket - these are awesome and I've had the same pair for about 5 years now.

I like the idea of cheep sunglasses. Lost way too many pairs of good ones over the years.

I was going to suggest to the poster that he dredge the bottom of just about any major waterway from Lake Havasu to Barnegat Bay and he'll find a few pairs of Maui Jims and Ray Bans I've donated during the years.

On a more serious note, if you think your eyes are cheap, buy cheap sunglasses. If not, buy the good (polarized) stuff.

Just don't ever look aft at speed. :)

Seaspecs Classic Polarized $50.00 or 3 for $100 @ seaspecs.com
I used them for my 80MPH Seadoo and they work great. Can't see very well if your eyelashes are on your eyeball.
They are actually surfing sun glasses but are aerodynamic and have a strap.

Maui Jim's and Rayban P's for me too. Once you try a set of Maui's you will never be able to wear cheap sunglasses again. I prefer glass lenses over polycarbonate lenses. They don't scratch as easy.

I have Oakley XX metal and SquarD Polarized Oakleys at $400.00 each. The Seaspecs are polarized and I cant tell the difference in the lenses.

this- my company buys these a 100 at a time, love them for the boat, they usally even come with a neck string to save them if they do fly off. I also keep some clear ones in the boat for night.