I've taken apart these new model j's to see what the problem is & it seems they've stopped using spring metal on the primary pressure control reed. The old reeds were made of a spring metal which- when removed from the regulator- would still be straight & would flex under pressure (even when the regulator was old & full of LP tar). These new reed valves come out bent, the little square rubber "gasket" missing or falling off, & the reed itself isn't flexible- even when the regulator is relatively new & within it's time frame for being returned under warranty.

I was so tired of replacing them under warranty that I ate the warranty on one & took it apart & the above is what I found. The Cobra regulator does away with the reed valve assy & has a more conventional spring & valve assy.