Sadly, the first time I drank out of it, I nearly roasted my lips off. It took 2 more days of drinking before I said "maybe I'll let this cool off before attempting to continue drinking it" and took off the top.
I have a zojirushi thermos, and I put coffee it in the morning and forgot about until about 5 pm. Thinking it had cooled down enough to drink, I open it open and took a big gulp and burned my tongue and throat. That thing keeps stuff hit for days.
