I have purchased several different tumblers from Frost Buddy and have nothing but great things to say about them all. They all keep my drinks cold or hot for long periods of time. The are not flimsy. I have no problems with leakage. My To Go Buddy has been my every day tumbler for my home made cold coffee brews, ice teas and when I purchase store made drinks they are awesome..just take the lid off and replace it with the silicone lid and it adjusts to various size cups, keeping your drink cold and icy for hours. I also have the Universal Buddy that holds various size cans which I love. It also has a lid to use for hot coffee..also a plus. I just purchased the Thick Buddy which is being used for my daily water and will be used like my To Go Buddy, it's just bigger. I have given my adult kids the To Go and Universal Buddy's and they all love them. Great product! Highly recommended!!