Yeah, I found the ring lands on the pistons to be the weak link. That said, if I did ever need to boost this thing, 6 psi would be more than enough. I say that, but who knows. Maybe one day I will drop new slugs in it and crank up the boost if I feel so inclined.
I think you are right it is more the pistons than the rods. There are a couple of guys that broke rods on challenger talk but not nearly as common as pistons. I would change them out as I would not be limited to 6lbs but that is just me.
