HEI in a Mopar?

Replacement HEI modules have not suffered from the "high RPM deterioration" for a very long time, possibly just after they were introduced.

The big advantage in my mind of a GM over Mopar box is don't have to worry about whether it's a 4 or 5 pin box, and you don't need a ballast. Even with a factory coil, they give you a little more "soup" and you can run a HP "E core" coil.