I have done extensive reaseach on this subject and have found cheap sunglasses will sink just as fast as expensive ones. Prescription glasses sink the fastest!:banghead::banghead::banghead:
In matter of one hour I lost my cheap glasses and friend lost his oakleys, neither one floats. I bought the http://www.xtremewearglasses.com/ and they look nice, have a strap and seem to be good quality. cant wait to try them on.