I've been using mine for a few months now for my coffee and tea. This thing is impossible to clean and there's always a strange smell coming from the lid.I've tried soaking in vinegar, detergent, baking soda, hot water, everything. It makes my stomach lurch to think what's growing in the lid mechanism.It did keep my liquids cold/hot, and never leaked, but it is clearly NOT safe for extended use. You can clean it religiously but things will get stuck and build up and grow some nasty bacteria. Even if it doesn't make you sick, your drinks will always taste strange.