Yea I saw those too (and thought those will be nice to drink out of as well)..
..glass is single-walled though, so I don't suppose it keeps the coffee hot at all?
The lid helps cut down on heat loss, and so it's probably a bit warmer than a normal ceramic mug, but not by that much. I prefer non-insulated mugs tbh, as I always manage to burn my mouth taking an unguarded sip from insulated containers.
Yea I saw those too (and thought those will be nice to drink out of as well)..
..glass is single-walled though, so I don't suppose it keeps the coffee hot at all?