Family & friends getting the Ember Mug but 1) expensive, b) one more gadget to plug in/recharge, c) one more thing to hand wash (yep, I'm lazy that way). So, while my experience w/ thermo glass major caution, they are FRAGILE. Yet, for the price, thought I'd give these a try. So far, 1) they do keep my coffee warm. 2) I preheat with a some water in the microwave for 1 minute and they withstand the microwave so far 3) they need to be handled carefully as they will break/crack easily if you bump tSee full review