I love my tumbler. It is such a great product.
I like the fact that the inside is smoother than some of the competitors, there's absolutely no sharp edge at the top, and the lid supplied is more leak-resistant than most. I'm not thrilled that the lid does not seem to be readily taken apart for cleaning. However, the lid diameter is one of the 'standard' one so that this lid is interchangeable with the ones from a number of other brands of the same size of tumbler. And the chill/heat retention seems pretty much the same as for my more expensive units. There have been reports that some individual units have insulation issues; that's probably an indication that their vacuum has been lost. This one remains fully insulation-functional after more than a month in use.
Love this tumblr, however the only minor thing I disliked is how because the lid has an open and close tab, water gets trapped under that part and mildew builds and eventually mold. I haven’t figured out how to get under that to clean it, so instead I bought a replacement lid with just an open spout.