Title: Lid plastic threads strip easily
Review: These steel mugs actually kept the coffee warm for four hours, but after six months of use, both of the mugs (which we had bought at Costco in 2011) had stripped the plastic threads off of the cap. If you tighten them just a little bit too much, the threads aren't solid enough to put up with the normal use... afterall, who doesn't tighten a travel mug! And tighten it well.
Is this product review negative?