Can anyone recommend a coffee thermos that actually works?

I need a two-cup coffee thermos to carry to work. So far I have bought two (stainless steel), but none of them seem to do the job. Both failed to keep my coffee hot from the time I pack my lunch box at 6:00 AM to the time I need to drink my second cup around 2:00 PM. Not that it is totally cold at that time, but warm coffee just doesn’t do it for me.
Am I asking for too much? Is it realistic to expect any such product to keep coffee hot for ±8 hrs.?
Does anyone know of a brand that actually keeps the coffee decently hot for that amount of time?
If you do, could you share the link, picture, brand, and/or product reference?