Polarised lenses from a genuine luxury designer are worth the investment because the lens technology is paired with expert frame design and actual optical science. The polarisation reduces glare without distorting colour which is particularly relevant if you spend time driving or near water. A designer brand will have invested in getting the lens quality right which means you are not just paying for the name. The frames themselves are engineered to hold expensive lenses properly. The combination of polarised technology and designer craftsmanship is why these cost more and why that cost is justified. These are the designer sunglasses that justify their investment through superior optical performance plus brand reliability.