Not all of the Johnny/Esther pools are extruded, only the higher end models.

As far as correctly installing the pool: I agree 100% but, it only takes a pinhole liner leak or gasket problem to cause a wall to rust out. Some brands are protected better than others against these problems. But even the most expensive steel pools can run into rust problems. We've sold 1000's of pools over the years and now we're selling mostly aluminum walls because of rust issues with the steel walls.

Josh