I have never left a product review online, but after relying so much on other reviews for purchases, it's definitely time to give back. This mug is exactly what I needed! I ALMOST bought another type of leakproof mug by another manufacturer as it got SO MANY great reviews...but at the end of the day, that mug (and so many others) maxes out at 16oz of coffee. I don't need 16 oz of coffee to stay hot all day long: I drink 16 oz of coffee in 2 hours...which leaves me bummed with no coffee until lunch time. THIS mug, the moJOEmo, got fewer reviews than the competition, but all of them seemed basically good, if not great. I am so glad I "chanced it." Since receiving the mug, I have only used it for one work day, but so far I am extremely pleased. It took me 4 hours to drink the full 22 ounces, and I will say it was hot 'til the last drop. If I had been drinking it more slowly, I believe the coffee still would have been hot, or at least warm...through 6 hours...maybe more (and this is with keeping the button open for drinking). I should mention that I did not "prep" the mug first, with hot water, before filling it with coffee. I work in a fairly large building and have to attend meetings in different rooms in various parts of the building, changing floors and carrying a laptop. I wanted a mug that would not spill and feed my keyboard (like my last, cheap mug, did) during these treks to and from meetings. The moJOEmo seems to fit the bill, with the button for drinking locked, and the screw cap on top. And the handle is helpful when juggling the mug and the laptop and running around the building, opening doors and going up-and-down stairs. This mug will not fit in a standard car cup-holder, but as we have an adapter type of thing, that fits into the cup holder and then expands to hold a larger mug, this isn't an issue for me. It does max out the adapter though. I do think you could leave this mug on the passenger seat (with the drinking button locked and screw cap on) and not worry about the mug flying off the seat and spilling. Even if it falls over, I don't think it will spill. Of course, this would make it tough to drink drink coffee while commuting. The fact that the mug is so wide, though, really makes it almost tip-proof. As another reviewer stated, when focused on the computer and reaching for the mug, there seems little chance of accidentally knocking it over. The pieces within the cap, for the button mechanism, are a little weird to get used to, for disassembling and cleaning, but I think after the first few tries, it will become second-nature. Disassembling and hand-washing every single day might take some work, but I tend to rinse daily, and wash on the weekends, so for me I don't think it will be an issue. One day of use and I am extremely pleased with this mug. So far I highly recommend it!