Do you prefer your water bottle to be made of metal, plastic, glass, or something else? Straw or no straw? How big would you want it? Should the bottle taper down in the bottom, or do you think the sided should stay vertical? Are any of you one of the few people who would like that weird rectangular bottle? Or maybe one of those squishy fold up ones for travel? No handle, flip up handle, mug style handle, or little loop?
Note that I am not affiliated with any water bottle company
At home I use a 1L glass bottle with straight sides and a wide opening, metal lid and a neoprene sleeve. It’s cheap, easy to clean and does its job.
The obvious downside is that it’s heavy and can break if you drop it but I don’t travel a lot so that’s fine for me.