ionMug Coffee Mug & Charging Coffee Mug Warmer Coaster, 12oz. Stainless Steel Coffee Mug with Lid, 3.5" x 3.5" x 5"

I bought this as a gift for my daughter. We've used Ember mugs for a few years and hers finally bit the dust. She doesn't like this mug. For one, it's plastic and she doesn't like drinking out of plastic. She also wishes it would keep the coffee at more than 145° but that's the hottest option with this mug. Most importantly, the mug is not submersible and that really makes it difficult to clean.

This does hold heat. It stays pretty hot, even when I don't put the lid on it. Which I don't like the lid. But my issue is it is so small. It says it holds 12 ounces. It does not. I can only brew 8 ounces in it and a little room for cream. And that fills it to the TOP. I can usually drink a 8 ounce cup of coffee a lot faster than a 12. So it would of been more beneficial if it had been a true 12 ounce cup size. Disappointed in the small cup size.