Just my 2 cents, I have this bottle since 2015 and I can recommend it without reservation.
I use it every day without exception, I fill it usually twice a day from my water filtering system, and I carry it with me everywhere, in a backpack, messenger bag, car, in a rucksack to forest hike or snowmobile ride. It fits in the largest pockets of my winter parka. The bottle has gone through a lot, and shows no sign of real wear.
I truly expect it to last my lifetime, maybe need to replace the silicon seal one day, probably because I will loose it after cleaning the bottle. I also have Klean Kanteen bottles, 27 and 64 oz, I like them a lot, but if I had to leave the Vargo 650ml bottle home, I would take my Vargo Bot 900ml rather than the Klean Kanteen 27oz. The KK27 is clearly heavier and bulkier, also top heavy, therefore slightly more likely to tip over.
If I only carried it once in a while, the weight difference would not necessarily justify the price difference. But as a daily use item it is absolutely worth it for me, I am very happy with my purchase!
**EDIT February 2019: The pop rivets holding the carrying handle failed after four years of daily use. It is easy to fix, I just need to find the smallest possible rivets, or drill the rivet holes slightly larger. I haven't done it yet because I don't need the handle for anything. For my use the functionality is 100% there, and I am still completely happy with my purchase.
***EDIT June 2019: Fixed the rivets, easy job. I got the smallest rivets from the hardware store and drilled the holes a tiny bit larger. Works like new.