After owning several pairs of Oakleys, I bought these mainly for their "anti-slip" piece of rubber on the nose, plus all the other positive comments I had heard about the resistant glass lenses and how great they were from other owners.I'm not a fan of Costa for a couple reasons.#1 The anti slip piece of material at the nose does help prevent slip. However, if you sweat like a normal person and it sweat runs down your nose, these sunglasses will slip right down just like any other. That's a little different from their website description saying that you can sweat all day and not have to worry about your sunglasses slipping off your head...#2 (This is what did it for me) These things didn't last. I've had these for less than a year and they just have not stood up to their claims. I take care of all my sunglasses so I was surprised when they started to deteriorate. The initial problem was a small drop onto GRASS. This had cracked one of the glass lenses which was claimed to be more durable to small drops/scratches than my Oakley plastic lenses. I had then noticed that the material at the nose was broken after normal folding and unfolding of the frames to put them on my face.So in my opinion, and considering the price, I think they fall short of the mark.There are plenty positive reviews on this product, but I would consider your options before buying. I was disappointed. Also, some of their policy on repairs/returns and what it costs is a little ridiculous...Quite possibly the best glasses I have put on my face.First, I'll just do a Costa overview.....they're the best active, outdoor, watersports sunglasses out there. When they say phrases like "lens technology", they mean it. I love another brand too. I won't say their name, but it rhymes with Schmaui Schmims. The Costa blow these out of the water (pun partially intended).These glasses though look amazing and fit so well. They're a very large fit. I have 3 other Costas. The Coba is a very big fit but these fit even large. The thing is, they fit sung on the ears so they stay in place. I don't even worry about wearing a retainer on these.....although I do, and you should too.exactly what I ordered and authentic! Even checked with Costa. They no longer make this model so I was super happy to find them and they were even cheaper than what I expected to pay for them.I tend to be frugal with my money when it comes to purchasing sunglasses. I take crazy good care of them, but find myself still purchasing the cheap, department store kind.I decided I really wanted a nice pair of polarized sunglasses this time around and came to find Costa Del Mar and a I could not be happier! The craftsmanship and design smarts are ever present. They fit wonderfully, are extremely comfortable. I plan to make these last me some time but, if the need arises, I'll be a Costa Del Mar customer for life!have had Ray-Bans and Maui Jims, and like these better......580P is outstanding clarity and the blue reflective perfect for bright sun. Just took these to Bali and wore them nonstop for two weeks..... after the first 30 minutes, didnt even know I had them on; clarity that good......Like other reviewers, these are large glasses but fit my large (fat) head well....... now, if I can keep from leaving them somewhere!I usually don't buy expense sunglasses. I lose them and there you go. But since I just had cataract surgery and do not need prescription glasses I decided to buy a nice pair of Sunglasses. After reading other reviews I decided on these and I really like them. Good construction, very clear and like the blue lenses. So I recommend them.Excellent glasses. One of the few makes that will fit my huge round head, and not look flexed out. Amazing contrast with the amber lenses, but still dark enough to be used as all around shades. Amazon service was tops, ordered in the afternoon, and received at 10:30 the next day; extra shipping charge of 3 bucks was well spent.Man these things improve contrast. Try different pairs in a store so you know what fits the way you like first, but Costa makes dozens of different pairs to fit different faces.580G lenses make the world look so good I forgot Trump and Hillary are our choices this cycle.Jokes aside, I can spotfish like a mother f***er everything is so clear and contrasting.Beautiful lense' but agree with YouTube review frames cause discomfort after long periods of wearing. Where I do not find I ever have that issue with Oakley. Lense' are exactly as advertised and worth the sale price. With better frames these would be 5 starGreat glasses, fast shipping. I bought the 580g lenses, they are the absolute best for my use, fishing.Excelente visión y proteccion