I Have been riding for a little over 50 years, and this tank bag is the one that is "just right"
1. Keeps water ice cold for ~8 hours: It may keep it cold longer, but above 95 deg, I drink the entire contents prior to 8 hrs.. It effectively Keeps the heat fatigue away.
2. Just the right size: Tank bags are either convenient (too small) or luggage (too big). Compound that with access issues getting gas 3-4 times a day. The Thirsty rock Hydration tank bag is just right. Holds a lot of water and just enough extra space for convenient essentials. I purchased the off road version on advice from dan and attached a clear full size map case.. My bike has a non-metal tank, so the thirsty rock zip-tied to a kriega tank mount. note, this set up provides sufficent space for my maps and is super convenient getting gas. The Thirsty rock tank bag has well thought out and flexible mounting methods
3. Super high quality.
4. Great Customer support.