Bests & Worsts Reviews from Amazon

WOW!WOW!WOW! Let me start off by saying I was going to return this bottle. I found the Nature Flask. Which was cheaper and had a copper lining. But I thought it weird that it had a 5 star rating. After ordering one I did more research and found some sketchy, broken up English, in the reviews, with periods missing. So I dug in deeper. 1) Their copper layering is good up to 35 hours cold/18 hot. Coldest water bottle is rated 36+ without the extra layer. 2) NF got a ding on a star because it dents easily. Coldest water bottle is made durable for athletes and people on the go. I partially freeze the water in plastic bottles (about 1 hour depending on freezer temps). As I break the ice from the edge I get shards. Picture is 28 hours later, it still has ice. So I have every confidence in the 36+ hours claim. Water is colder than my Super Sparrow and Kleen Kanteen. About the whistling; I do have a standard mouth cap and it whistles like an english BOBBY. This wide mouth, even though not silent, does not seem to whistle. You can hear the air bubbles percolating in the bottle, but no whistling. Honestly, could not be happier with my purchase!!! Highly recommend!!!