Primus Commuter Vacuum Insulated Mug - Stainless Steel, 14 fl.oz.

Haven't had the same issues that other's are claiming... The screw-on lid is secure, to say the least, and the push-button sip valve seems to work just fine. Also, pretty tough. Already dropped in the parking lot a few times, no damage. The greatest feature - heat retention is excellent. Here's an example, made tea (at altitude, so, lower boiling point), drove two hours, drank 1/2 of it, skied all day, it was still warm (not hot) when I got back in the car. Would have given it 5 stars, but the lid assembly can get really tight (also means good seal though), and it can be a little tough to get off if tightened too much. Have two, looking to buy more.

The product is impresssive as it does keep the contents hot for a long time and has better fluid retention properties than most other cups found out there. My problem is the open/close spring loaded detent mechanism. It does not always work. It will open but then will not close again. I have to unscrew the lid to have it operate, and then it will only work once, and I have to unscrew the top again. Not good when you are driving, but contents are hot!!

I have 2 of these, that is correct I got Jacked for [$]. At first I thought awesome, does not leak, keeps things hot or cold forever. Then after about 3 months of using them each day, it starts. Lid pops off on occasion, so don't trust it in the bag. Both of the seals leak whether your driving or trying to drink from it. I contacted the so called manufacturer (really made in China) and they basically said, oh sorry contact who you bought it from. Yea I am sure the local outdoor place will rush to take these back. AND I followed all of the care instructions, never been in a dish machine. Just don't waste your money on this. Might have been worth [$] before moving production to China.

WOW !!! it sure keeps things HOT 2hrs later the tea was still almost to hot to drink. Best cup I've ever owned.

Keeps the coffee warm just about all day! and I work outside.

Mostly we use these for commuting but weekend mornings in bed are great - no spilling! These mugs keep things hot, even in very cold weather. We have tried many so-called thermal mugs and these are the best. It took a little getting used to the button in the lid but it works great now that the operators are trained ;) I would not put the cup part in the dishwasher because it looks like the black paint would chip off. I may have to put the lids in once in awhile. For now I just shake them with soapy water inside.

The lid takes careful alignment to screw on but aside from that it's a well-made, solid piece of construction. It doesn't leak.

Holds 14 ounces. Wish it held 20 ounces. Otherwise, love it. Keeps my coffee really hot and does not spill.

I've collected a few mugs over the years, and this mug is by far the best. It keeps my coffee hot for quite a while, and it really is spill proof.

Keeps coffee warm longer than any other mug I've owned. You can tell it looses most of its heat through the lid. Overall a purdy good mug and spill proof. Like i said....it keeps my coffee longer than any other mug I've owned and I've owned a few over the years.