Most helpful critical review
Did not meet expectations
on December 10, 2011
I purchased a set of these mugs as I wanted a cool-looking clear mug that would keep my drink warmer longer.
The mugs are nice to drink from and look good on top of the espresso machine. Later, in order to determine how effective they are at retaining heat I did a hot water temperature test, where I measured water temperature over time as the hot water cooled as compared to a standard single-wall mug. The bodum mug performed only slightly better (and I mean slightly). One nice thing is the outer wall of the mug does not get hot, the bad thing about this is if you're using the cup warming tray on your espresso machine to warm these mugs up the heat does not transfer to the inside wall easily - lessening the effect.
After 1 week both mugs are now broken. The inside glass wall is paper thin. One I dropped from a height of about 18in into my dish tray (my fault) and the other broke washing it. There is also a breather on the bottom which lets moisture inside the air cavity.
In the end I would much rather have a clear, thick, single-wall mug capable of sustaining long term abuse.