It holds up very well. I've used it in some pretty hot trips (Canyonlands, Capitol Reef, and Mojave Road all during June or July) and it expands as expected. It's never leaked, but it will vent a little when it gets really hot out. It's also relatively easy to transfer gas to the FJ using a jiggler siphon (although I learned on this trip that it's easier to get maximum transfer when the tubing is warm and pliable than when it's cold and doesn't want to unwind). I think it's an excellent solution.I never used one for that application. How well does it hold up to heat, expansion, leaking? I’ve beaten them around on river boats but never to the extent of what you are doing with it. Just looking for some feedback as it might be a viable solution for some of my trips.