I really like this mug. People say it does not keep the contents warm over a long period of time, but PEOPLE, it is a 12 oz cup! How long do you want to suck on a small cup of coffee like that? If you want something that will hold your coffee longer, get a large thermos! For me, this mug kept my coffee very hot over the 45 minutes it took me to drink it, WAY longer than a large non-insulated mug would have! I am very pleased!