I had a Sport Locker on the Mainland that I stored all my non-sailing stuff in. It held up fine. I never lost a lid as I always locked it before travel. If I had to do it again I'd get the Max as the Sport Locker has to be assembled.

Reading some of the other posts an even better solution would be to fabricate one out of aluminum. It'll last for ever and it's much lighter than steel. Plus, when the angle of the sun is right you can blind the tailgater behind you.