Bests & Worsts Reviews from Amazon

Works flawlessly, doesn't leak, and keeps my coffee hot for an extremely long amount of time. Like, a REALLY long time. The only reason I didn't give it 5 stars, is because the inside of the cap is an absolute nightmare to clean. There are a few moving parts, and a ton of nooks and crannies for bacteria and all sorts of general-use coffee scum to hide in. You can pull back some of the operating parts to get a better angle to wash the inside, but it doesn't help as much as it needs to, and once opened it's still really in your way. The threads have the same problem. They are semi-covered by the outside sheath and you have to really get in there with a Q-tip or a toothbrush to get it sparkling. Pictures are showing the underside of the screw cap un"opened" and opened. Hopefully you can see what I mean about the nooks and crannies, they get very disgusting very quickly if not thoroughly cleaned with hot water and soap. Likewise, the soap gets stuck in there too and will make your drinks taste like it unless you diligently wash it out as well. I still very much recommend this product, and will purchase another if this one stops functioning.