On my SSS I recently tried it, and it works fine.
On a defense gun I can see how a heavy dbl leg might save you if (and it does happen) a leg of a spring breaks and the one left still works it, well, just like mine.
Just make sure you get reliable ignition with several types of ammo and you are good.
The only downside I can see on a new gun is that the dbl spring in the heavier mode will help to burnish in the wear surfaces on the parts. Maybe consider using it with the dbl leg for a while just for that (200 rounds, or so), then unhook one and go.