The Big Mouth is the best bottle I have ever used. I can show you literally dozens of rotted out, moldy, beat up, tore up nasty bottles. All remnant of my previous bottle use. I have used just about every style of water bottle, different lids, different shapes, different materials, disposables, etc. None have worked as well or lasted long enough to save me money.
The Big Mouth has lasted me two years thus far. The design has long since worn off of it, but the bottle is still just as sound as the day I bought it. It has never leaked, cracked or spilled. I can guzzle water when I am piling on speed down a racy straight-away and the textured surface ensures that I have a firm grip and I am not going fumble the bottle causing me to have to go back for it.
I have left the bottle sitting for a week, gathering a nicely developed colony of penicillin. Then picked it up and easily scrubbed it out for use within minutes. I am not a "maintenance" person. My bottles tend to gather funk so, an easily cleaned bottle is very important.
It's durability is excellent. My "Big Mouth" has been knocked off the roof of my car while setting up my bike, I once missed my bottle cage and sent the bottle hurtling into the street at 27 miles per hour, and I have ridden with it in temperatures as low as 15 degrees fahrenheit. It remains leak proof. And if anyone were to challenge this claim, I would invite them to use it. I still have it sitting on my counter waiting to receive electrolyte/carbohydrate filled cytomax and to quench my thirst.