I've owned all the fancy expensive mugs. Liked many. But this is the only one that, with top on and slid "closed" then forgotten, 2 hours later my coffee and tea are still piping hot! I do not wash in dishwasher, always by hand. Not one leak, though as an intelligent person I wouldn't push too far and take a chance anyway. For a work or camp mug this works great. Got the sparkly pink and navy-love em!It's quality double wall stainless steel! Love that it's easy to hold and keeps drinks hot/cold for hours! Not to mention the rose gold is pretty; I gifted that one (to an elderly person who loves it) and kept the other. Seems spill proof, but I don't travel with it. Overall, I'm happy with this purchase.I reviewed these mugs recently with a complaint that I couldn't figure out a way to get the lids clean. If you wonder if the sellers read the reviews, this one does! They clarified the instructions for taking the lid apart to clean so that even I could figure it out. Kudos to SUNWILLPurchased as a gift and it is great. Keeps coffee hot! My only strife is that it does not fit in cup holders but I knew that before purchasing which is why I am still giving 5 stars.It was a Birthday gift to my son and he loves it! It keeps his coffee hot without reheating and the lid is great when he sits out on the patio for morning coffee.Bueno lo compre para que mi esposa tuviera su chocolate caliente. Es tan efectivo que ella ahora lo tiene que enfriar porque dice que dura mucho tiempo caliente y se puede quemar. Lo recomiendo mucho. Bueno, pero hay que decir que todos estos productos duran mas o menos de dos (2) a cuatro (4) horas de calor y de dos (2) a ocho (8) horas máximo de frio (prueba en la vida real).It's easy to clean. But the lids on all of these have a lid that is hard to drink from. And I would like them to be insulated. Better to have a screw out lid that is insulated.These work as described at a good price. Keeps my tea hot for a long timeGood mug- not as heavy duty as some, hefty price, not thrilled with it’s keeping coffee warm, just ok.Mom loves it got it for her for Christmas but came after, took a month or so but after I got it mom loved it. The people were pretty nice as well got in touch with them because of shipping issuesThe cups arrived ahead of the schedule delivery date. Quality of cups appears quite good and as advertised.