Keeps beverages cold even in hot sun
341225
I use this to keep bottled water cold while playing golf.  I'm out in hot temperatures for 5 hours and the water remains cool.  It hooks on the back of my golf cart and is very easy to use.  (I do put one frozen bottle of water in with the others to keep it colder).
4183918
This water bottle holds a lot of water and keeps it cold all day! I don't put ice in mine, just cold water from my frige and it stays just as cold as when I  fill it up in the morning. I work outside in the desert where temps in the summer reach over 110 degrees and it's necessary to have cold water. I found another water bottle early on and really liked it but now can't find it anywhere so I thought I would try thermo tank. I didn't think I would be able to find anything as good as my last bottle but thermo tank has proven to be just as good if not better.  It holds more water than most bottles and it has a great design. I especially like that the drinking area isn't so big so you don't get a deluge of water spilling out everywhere when you try to drink.
3333240
Excellent product. Keeps drinks cool for a day's worth of hot summer outdoor activities.  Haven't really used it for hot beverages yet.
2081669
Kept my frozen drink from melting in the hot sun. I was playing water volleyball for hours and my drink seemed to actual get icy.
3104397
Keeps drinks cold for at least an hour outside in the heat of Texas summers. Holds a full 16oz, unlike many "pint glasses" that hold 14oz.
893420
This is the best I have found for keeping water ice cold. And I mean literally. I have left this sitting in the sun in a car in Florida for 5 hours and come back to still have ice water. The bag and included carabiner are a nice touch. Only 2 very minor improvements I'd like to see: a straw that fits a little better (it slides loose in the bottle occasionally) and a change in shape that would allow it to fit in a cup holder. The 24 oz bottle will fit (in a large cup holder, not the small ones that only fit non-insulated bottles), but the 32 oz bottle base is too thick even for the cup holder in my van. Still, even with those very minor drawbacks, this is THE best insulated water bottle I've found (and I've bought 4 others in my search in the last month alone).
762635
This is the second water bottle I've purchased from SM.  I use one for outdoor sports that sits in the sun for several hours and it amazingly keeps my water cold.  The second one I purchased for my son.  He's in marching band and is always complaining of drinking warm/hot water from a regular water bottle.  He was amazed that he could leave his SM water bottle on the bus in the hot sun and still have ice in his water.  Great product for half the price of other Flasks.
4416400
One thing that separates this product from others that are similar is the fact that it is vacuum insulated.  This allows it to keep drinks cold during the hot summer day (hot drinks are not recommended).  In addition, it has a one-touch spigot system that allows you to hold the bottle in one hand, press the button with your index finger, and get a drink WITHOUT putting your lips on the bottle.  I like that because it makes sharing much less uncomfortable with regard to germs, etc.

The only reason for the four stars is that it's not really designed for hot drinks.  I have no idea why, perhaps they don't want you to burn yourself, or the plastic won't hold up to hot liquids, or what.  But I have a Thermos for that, so overall not a really big deal.  It seems very durable.
4036901
No condensation and keeps drinks colder longer than glass.
2574672
The problem with most mugs is that they seem to have no insulation to keep the beverage hot. Many of them are so poorly insulated that their exterior becomes uncomfortably warm.  After years of searching for a really good mug I finally found this one which almost all reviewers liked a lot.  Based on the reviews I ordered one and found it to even exceed the highly favorable reviews.  This is unquestionably the best mug on the market.  The exterior stays cool, thus keeping a beverage hot all day.  At a 22 oz. capacity it holds enough for all day.  The open/close mechanism in the lid works perfectly.  The auxiliary screw-on cover is great for mobility.  One caveat is that there are some in the "pipeline" with defective insulation which allows the beverage to cool quickly.  After liking the first one so well, I ordered a second one which had this problem.  I contacted the company and they were extremely responsive at getting another non-defective one to me.  I subsequently ordered a third one and it was just fine.
3904074
Held the beer cold even in the Florida summer sun. Will buy more as gifts.
3923433
Works great. Doesn't keep ice for 5 days as some suggest, but provides ice cold drink  for around 2 days in the hot Florida sun. I keep it in the bed of my truck in direct sun and it still stays cold for 2 days easy. No problem so far with the lid flying off even at 75mph highway speeds.
112620
I love this insulated beverage container. I have made ice coffee in the morning with some ice cubes in it, bring it out during morning break and leave it in the car in 90+ degree weather for hours, come back and it is still ice cold. I have not used it for hot beverages yet, but would expect similar results.
4451975
This is a great mug and it works as advertised.  It keeps my drinks hot for my trip, and I don't worry about spilling (it hasn't).  The size is just right for me (fits a good sized drink), and the design is well thought out.  After tightening the lid to keep it from spilling, it can be a little hard to turn the lid a bit so you can drink.  However, it isn't too bad and that's a small price to pay for not having spills.

I have also put ice in it for trips and it keeps the ice frozen for a long time.  This is useful if you stop and just want water, or if you're driving in the heat and have brought along some bottled pop that is no longer cold.  Just pour into the cup and enjoy a cold drink.

Recommended!
549806
Works great...keeps my drinks cold as advertised.
1608051
Great mug - I fill it up in the morning with water and ice, and it stays cold all day long, even when left on the front seat of my car in the sun. My one complaint is that the rubber grip ring and plastic top actually get very hot in the sun. The aluminum sides also get hot but quickly cool off, leaving the odd sensation of gripping a burning hot thermos and drinking ice cold water from it.
818918
As promised, the flask kept ice water cold and crisp throughout a day-long hike in hot weather, and we were able to enjoy hot tea at sunset on a cold and windswept beach even though I'd brewed it in the morning and walked around the city all day.  It's a little heavier than the single-walled stainless steel flasks I've used in the past, but it's worth the extra weight to have cold or hot drinks after a long hike. I have both caps and enjoy both, though I do like the flip-top coffee lid for hot and cold drinks - it has never once leaked, and is a lot easier and quicker to open than the screw-top.  It has a slightly more reduced flow than I'd like, but not irritatingly small - and if I wanted to guzzle water, I could just unscrew the lid.  I was concerned that the 18 oz size would be too small, but it seems to work out well for my needs.  I can refill throughout the day at work, and for an afternoon hike it's not too small for me.  There's no metallic taste or smell, though I do sometimes put a little sprig of mint in the flask for a nice change.  I would - and have - recommended this flask to everyone looking for a flask that works, doesn't sweat (thanks to the double-wall), doesn't leak, and has a smart design.