has anyone nerded out on insulated water bottles lately?

I put a 2L Platypus in between my emergency down mittens in a hyperlite stuff sack.  Cinch stuff sack around lid area.  Adds zero weight to the program and keeps water warm throughout a day of backcountry skiing.  Two liter capacity versus a 1L bottle in a foam gizmo.

I did some tests on insulated water bottles on my blog here:

http://larsonweb.com/blog/?p=1815

As a Denali guide, I can say that it’s pretty standard to carry a nalgene in a neoprene cover, plus a thermos. Drink the nalgene first, thermos later. The thermos will be steamy hot long after the nalgene is slushy. Really only a couple ounces of weight difference between the 2 options.
For cragging, I guess if I just wanted warm Gatorade I’d bring a covered nalgene. If I wanted hot tea I’d bring a thermos.

https://www.youtube.com/watch?v=a6j1NJkNzwI

This guy gives a pretty comprehensive study of insulated bottles.  Lots of other great stuff on his channel that is really helpful.  Too bad he isn't a climber, he could do some great reviews.