Why is almost NONE of the discussion in this thread about Promethium??
First question, is it DC or Marvel Promethium. The marvel one from memory is a mystical metal that can hold power. IIRC one of Doom's armors was made from it.
DC Promethium is supposed to be perpetual. In otherwords it is strengthened y the force applied to it. It's supposed to be stronger when greater force is applied. It should by rights be stronger if Superman was trying to bend it than if WW was. It was supposed to do the same with energy. a nuclear reactor with some in it's core was supposed to be able to generate limitless energy.
I'd say the marvel one is close to as strong. The DC one isn't.