I actually used a Polar Bottle back when I started mountain biking about 15 years ago. I wasn't impressed. The bottle's reflective insulation is supposed to keep your drink colder, longer, but I didn't find that it worked any better than a regular water bottle.
So I wouldn't recommend buying one based solely on the insulation promises, though it's been a long time since I've used one, and things change. But, if you like to take your best canine friend with you wherever you go, you may want to consider a Polar Bottle.
Product Architects, Inc., maker of the Polar Bottle, is running a promotion between now and December 22 whereby customers can order bottles with pictures of their pets on them--great for a gift to yourself or someone else.
The bottles cost $20, and $5 from each purchase will be donated to the Humane Society of Boulder Valley. Seems like you can't go wrong.
You can upload photos and order at www.polarbottle.com/pet-photo-bottle.