Bests & Worsts Reviews from Amazon

To start being green I tried to avoid plastic altogether. But most bottles have a plastic top, always claiming to be BPA free. That's fine. That being said, the first difference between the Klean Kanteen and the Takeya is that the Klean Kanteen top seals by going within the bottle. Which may create a better seal in theory (the Takeya does NOT leak), but it becomes irritating when you have accidentally put too much liquid, twist on the cap only to overflow all over! The second bad thing about the Klean Kanteen seal is that while it sits in your bottle the seal is coming in contact with your liquid. Not to gross anyone out, but most of the times I "washed" my bottle by dumping out the residual water, rinsing in hot water and refilling. Unfortunately this was not good enough. On a random inspection I noticed black lines of what I assume to be mold growing around the rubberized seal... eww. The Takeya bottle screws on the outside, which means minimal fluid contact with your seal, and no overfilling of your bottle! The cap on the Klean Kanteen is rounded with a top loop for carrying and on more than one occasion I guess I over-tightened the cap and could not easily remove it! I instead had to put my finger, or an instrument if really tight, through the loop and use it as leverage. Awkward, and painful. The Takeya top is a square with rounded edges giving you a little bit to work with to twist off the top. The Takeya has s loop separate from the cap for carrying. Another issue is that you have to buy a separate neoprene carrier for your Klean Kanteen if you want it to stay cold longer and not have to handle the cold metal. I highly recommend the carrier, but the Takeya comes with a silicon sleeve already for gripping. A bonus is, if you have the Klean Kanteen first, my neoprene sleeve for the 27oz. (with a little work) fits the Takeya! So I now have an extra cover to save the glass. The Takeya doesn't stay as cold since it is glass, but the other benefits definitely out-way this set back. The mouth on the Takeya is PERFECTLY sized for sipping and/or chugging. The Klean Kanteen has a large opening that lends its size for ice cubes, but constant spilling all over myself. (On a side note, I also hated hitting the metal on my teeth while drinking, glass is less awkward and irritating.) Regular ice cubes from the "make-it-yourself" trays do not fit in the Takeya, but I fill the tray half the height and they slide right in. I have dropped my Klean Kanteen multiple times resulting in paint chips and dents, but it is very resilient and never sprung a leak. The Takeya fits in a car cup holder also! For my first attempt at going green I loved my Klean Kanteen, but now that I have felt and tasted a Takeya glass bottle... I would never go back!! If you're unsure, I hope this helps in making the choice for you. P.s. I know weight has been stated as an issue, but I honestly have not noticed a SERIOUS difference between the two, but I have always carried around something.