"Ounces turn into pounds and pounds turn into pain."
The weight of water carriers adds up fast when you start to carry more than one.
The Nalgene
Oasis canteen is patterned after the classic US military canteen. It is a little more flexible but still weighs a little over 4.5 ounces. IIRC the popular 32-ounce Nalgene Lexan bottles weigh 5 or 6 ounces. Too much dead weight in my book.
The Gatorade bottles are a good, tough, cheap and lighter alternative. I've settled on the
1-liter AquaFina bottle as my canteen of choice. If you cut off the label and the remaining ring from the cap's initial seal, it weighs right at 1 ounce. It is pleny tough and the wid(er) opening is handy.
I hear they even come pre-filled with water...!