I loved this mug for a while. It was leakproof, which was basically all I asked of it. I dutifully scrubbed it by hand after each use, making sure to rinse the lid thoroughly. Despite my efforts, I began noticing what I can only describe as The Stench -- a heave-inducing mix of old coffee, old milk, old whatever else I put in there. No amount of cleaning removed The Stench. I tried rinsing with vinegar, soaking in soapy water, etc. Every now and then I would take the mug out of the cupboard, hoping The Stench had dissipated, but it was still there.Then I read other reviews on Amazon about finding filthy globs of mildewy muck inside the lid, and in one case...maggots! MAGGOTS! IN YOUR COMMUTER MUG! That was the last straw. Sayonara, maggot factory.