Outdoor Research sells a very nice insulated soft carrier that uses a belt loop or molle connection for that Nalgene 32 oz. water bottle. This would be good for the cold times.
Those are nice, and necessary, once it get's cold enough. I also have a neoprene version from Nalgene which leaves the top exposed. More of a holster style still good below freezing, but not as much.
Thinking your neoprene holster style would help keep drink cooler during the hot summer. I looked at the Nalgene water bottles at Target today. The polycarbonate (#7 plastic) was about $10, so thinking the honorable Treeguy does have the HDPE (#2) which a lot of us think is better for continual water transport, storage and use.
Yeah I would be surprised to see the HDPE in a retail store. I only see them online, probably because they're kinda ugly with that milky white color. They need the fancy purple, blue, green etc. transparent bright colors to sell in stores. They used to be polycarbonate but now made from Tritan. A "safer" plastic, until another 20 years passes and they say that causes ___(fill in the blank)___.
Some big white plastic Nalgene bottle. Maybe 32 oz. Cost about $4.