The stainless steel Nalgene bottle is one of the very few Nalgene products that isn't made in the USA. It's a Chinese product. It is very robust and pretty heavy.
Obviously constructed to last a lifetime.
Different to others you have here outside around the neck a deep channel for the lid attaching cord. And here you could as well put in a stainless wire snare that you can easily make in every good boat shop.
With that you can hang it under a tripod if you like.
So far we talk about round bottles it is surely the best available construction on the world market. There is a Lixada stainless steel mug, 750 ml with bail and butterfly handles, that nests with it. That's a nice kit without any doubt and you get several bottle pouches for that if you want. I guess the TBS mug is the same and hope that I once get the answer after a meeting of the members of this forum. Theoretically one could be better than the other, but I guess they come from the same Chinese factory.
But I have to tell you that I recently played around with all my different bottles and compared them. In my opinion the kidney shaped military field bottle with nesting mug is the best option for several reasons:
It doesn't roll around on the table, in the car, wherever. That means it's unlikely that it will fall and get dented. It fits better on the belt but also better into side pouches of rucksacks if they are large enough.
You can better grab it and the mugs tend to have a better size.
The problem is, that there are nearly no NATO issued metal field bottles left over, apart from the very well constructed German army bottle with for our use pretty idiotic two mugs. And it's a bit too small for my taste. That thing is made of aluminium.
There are easily available old French army aluminium bottles with wide opening and plastic lid and 1,3 litres capacity but they don't nest correctly with the newer original steel mugs that are made for the current French army plastic bottle, which is in my opinion the currently best option on the market. Plastic bottle and steel mug are made by De Buyer in Lorraine in outstanding good quality and because it's the newest NATO issued bottle they eliminated the construction faults of the others here. I think it is my best field bottle and I have quite a lot of different models. But you get only wool lined cotton covers for it. There is no Nylon pouch for it. I asked everywhere around, really everywhere and became sure that a issued original Nylon pouch for it doesn't exist. In your position I would gift him this (2x) and additional a 1,8 litres pathfinder bush pot. That's a sensible realistical solution, and the best currently available choice that I know. I would give him immediatly two French army plastic bottles (new), and two nesting steel mugs (new), the 1,8 litres steel pot from Canterbury (new) and a Dutch army steel mess kit (used) after British pattern. That's a nice student kitchen at home as well as with a friend outdoors. 18 years old people should get equipment for a couple in my opinion.
The old French alu bottle has stupidly many threads. You screw and screw and screw ... and the alu cup is an alu cup and as you know they are horrible because you burn your lips.
What I don't own is the Austrian army aluminium bottle with plastic lid, steel mug and nylon pouch. It looks very interesting! The mug handle folds under the cup though, no idea if that's practical. The US army changed to butterfly handles.
Is the surely non shock proof Keith titanium canteen worth the money?
I rather think not, also because you also here get a pouch problem.
Mr Canterburry offers a stainless steel canteen that looks good. In the beginning the lids broke but I guess they fixed the problem. China made of course. But there is also a copy of the Swedish army mess kit in the shop, that looks interesting.
Do we boil water in a steel bottle?
No, we don't because they don't stand very stable on a camping stove and especially because there are no handles to take it away from the fire.
In my opinion it's a survival tip for those who have no army field bottle with nesting steel mug and no pot with bail handle or German or Swedish mess kit
Boiling water in a steel bottle is in my opinion like building lean to shelters from dead wood and leaves. I have nothing against it but I don't do that. Why should I?