I am a huge fan of Serengeti sunglasses but this model was not meant to be. New, out of the box they are light crisp lenses but dust quickly started sticking to the inside of the lenses and when I tried to clean it with the cloth supplied I discovered the inside surface had some weird tacky film to it.
I contacted the seller and tried their suggestions but ultimately returned them with the sticky film. Worth noting, and I'm no expert but a step may have been missed in the finishing process for these lenses. I noticed when wearing them that I could see a lot of reflections which I've never seen on any of my other Serengeti glasses.

I'm ordering a different model and staying with the tried and true model I love. the Maestrale.