The instructions recommend a flat bottom cup and my office cup has a pretty typical indent (SEE PHOTO

then add more hot beverage to a half cold cup that I then must microwave to try to warm-up to have it cool down even faster

Best cup warmer I have used

Product does not keep coffee hotter than low warm, Still has to be heated to a higher temp, If a restaurant served coffee at that temperature, I would ask them to bring me a steaming hot cup.

so if my cup is still warm to the touch..it shows rhis warmer isnt even worth my money i paid for

it does not keep my coffee warm at all..i can put it on high and touch the bottom pf my cup and its not even hot

I always get busy and let my second cup of coffee get cold before I notice

No more trips to the microwave, no more compromising that fresh cup of joe flavor!Warms well, doesn't take up too much space, has a nice metallic finish that can match any professional desk decor.

She was always throwing out half a cup of coffee because it got cold before she could finish it, then this warmer comes into the picture and she raves about a nice hot cup all the way through.