So

Since I'm currently on a shopping spree for my adventures backpacking, trekking, bivying and so on, I'm looking for certain items where I feel weight savings are in order.


My current plan is the following:
- Bring a SteriPEN to areas where there's a risk for human contamination in the drinking water

- Get a Katadyn Befree filter with Hydrapak Seeker 2L bottle (a little over 100g in total and super compact when collapsed) to filter suspicious/muddy water on the go.

- Bring two 1 Liter drinking bottles to be refilled with filtered water from the hydrapak en route


When there's no knowing whether there will be additional water sources ahead, I can always put the hydrapak filled into the backpack and have a total of 4 L capacity with me.



Now, my problem is the drinking bottle...

Obviously, I would love to get an insulated stainless steel bottle so I can bring warm/cold beverages along with me when needed.
However, a Hydroflask 32oz insulated stainless steel flask weighs 15.7 ounces, that's 450 grams, empty! (triple the weight of a simple aluminium flask!)


Plastic bottles aren't really an option, since the "BPA-free" marketing blurb doesn't mean anything.. https://www.livescience.com/63592-bpa-free-plastic-dangers.html
I would, therefore, only use the hydrapak bottle to quickly filter some water, or in emergency situations, where large amounts of water need to be transported, and not store water inside for a long period.


Aluminium has me worried as well, despite the fact that I use antitranspirants daily. (So far, there's no evidence, that aluminium enters into your bloodstream through undamaged skin; that's why it's not advisable to apply antitranspirants after shaving.) The aluminium, while somewhat inert, will enter the water in small quantities and get into your bloodstream when absorbed through the stomach walls.




A Primus insulated expedition S/S bottle weighs 600 grams, whereas the regular stainless steel drinking bottle is 240g. A Salewa aluminium drinking bottle is 140g, and the Primus Tritan plastic bottle is 180g.. So, there's a ton of weight that can be saved with two 1 liter drinking bottles...


I'm open for your suggestions, because I find it really hard to make up my mind in this case..

Should I get one of the insulated steel bottles and one ultralight non-insulated bottle, or two insulated ones, or two non-insulated ones?!


Re pricing: I don't really want to set an upper limit.
If the bottle is sturdy and lasts me 10 years, I'll gladly pay a premium for it.

Also, I need the bottle to be available in Europe!



I have one of these chinese bottles (like Chilly's... Since it looks identical, it must be a Chinese manufacturer that makes them, because I bought it from a Swiss outdoor retailer and it carries their own branding) and the quality is so bad, that it's foot is skewed after setting it down a little too roughly once. I never dropped it and always treat it like a glass bottle (it has no signs of use or anything, although I use it daily for work).

I don't particularly trust aluminium to last very long and the plastic stuff definitely won't last before it starts to taste badly.