Bests & Worsts Reviews from Amazon

This is the best coffee mug I have ever owned. bottom line: lives up to its promise. I actually forgot this mug in my office before a meeting and when I came back for it six hours later the coffee was still STEAMING. Bewildered by some of the negative comments... Why invest the time to log on to Amazon and complain but not take 67 seconds to read the enclosed instructions?? The rubber on the lid tastes funny? Wash the lid with soap and water before first use... AS INSTRUCTED. The cup overflows when you put the top on? Do not put liquid past the fill-line... AS INSTRUCTED. Yes, you just about fit an entire Dunkin XL (24 oz) inside if you go past the fill line, but this is sold as a TWENTY oz cup. So imagine that, overfilling it can cause it to overflow! Who knew? I burned myself because the coffee was too hot and/or I didn't know how to control the flow of liquid...? Surely that's a joke. Hot coffee is hot and this product is designed to keep it hot for a long time (which it does better than any other competing product I have tried in 2 decades). As for use... The, err, "drinking slit" (sorry, unfamiliar with technical coffee kid nomenclature) is exactly the same shape and location as that on every take-out coffee lid everywhere on earth. If you can't figure out how it works, go to the nearest Dunkin donuts or Starbucks or freaking McCafe and watch someone else drink a coffee. It is a fairly intuitive process.