A word of warning about freezing coolers. The outer shell gets brittle when frozen and can crack if bumped around while it is still super cold and I don't think you gain that much. You can get just about as much additional ice life by just freezing your own blocks and precooling your cooler with an ice block the day before you pack it. Do not buy 7-11 or grocery store ice (it is crap). I bought a freezer chest just for rafting ice and frozen food and it made a huge difference freezing my own ice. Did a 28 day trip (22 on the river) on the GC from the time I left till back home. Packed a day 12 till day 18 frozen cooler and still had Ice (not much) when I got back. Another thing I learned was to keep the freezer at least half full of block ice at all times and it costs less to run. That's my 2 cents.
Time is like a river. You cannot touch the water twice, because the flow that has passed will never pass again. Enjoy every moment of life on or off the river.