I've had a flip-top zojirushi for more than 5 years. It replaced one of the same, the lid eventually cracked after about 6 years from being dropped so many times. This one has been dropped less. I have a new one in the pantry for when this one eventually dies. It still insulates as well as the day I bought it and the flip mechanism is just as satisfying.

My criteria: pocketable (not huge diameter), insulated, covered to keep work dust out of it. Sometimes the metal bottom gets a bulging dent when I drop it, I use a hammer to flatten it back out.