I'm not sure what the point to going to a 4life type of coolant is. Every 5 years or so you'll be changing the water pump and are you going to save and put back in the coolant that comes out? Whenever I take coolant out of an engine there's dirt in it or I get dirt in it, are you going to strain/clean the coolant? It seems easier to me to just change the coolant every time you change the water pump, and probably cheaper as well.
The way I see it the big issue would be if you needed a top-up while away from home. You would be forced to use water and that would ruin the coolant.