Very good for its price. It is indeed leak proof, I use it daily, at the gym, at work, and there has never been the slightest leakage inside the bags I carried it in. Additionally, as for its appearance, it is elegant and practical compared to similar products that are usually quite bulky. I don't know how long it will last, I have had it for 2 months with daily use and it has not shown any wear and tear, neither on the rubber of the lid nor on the color on the outside.