i have had them all, i'm over trying different glasses now.... costa is just the best. i have had several pair of MJ's which are great glasses, but they don't clean easily (smear rather than clean) and are more prone to scratch vs comparable costas. i have a few pair of costas currently, and a couple pair are several years old.
you can usually find good deals on costas if you look around (sierra is a good starting point if shopping)
if you don't want to spend the money, natives are great for mid priced glasses.... Revo also have very good lenses, and Serengeti are a sleeper.... used to be pretty popular, but not so much anymore, but they are great for the money, and are very durable lenses and clean easily.
i think just shopping around for a good deal and buying costas is a no brainer, but it's not the only good polarized glasses.... they are the best, and can be found for good deals.... i will never buy another brand at this point, because i have done the testing myself with probably 25 pairs of high end polarized glasses, and working on the ocean my whole life