Greetings,
I have a 38 S&W shell plate. Not the 38 Special; but, 38 S&W. The 38 S&W case diameter is slightly larger than a 38 Special.
With a set of 38 Super/ACP dies, you would be all set.
Only question is whether or not the 38 S&W shell plate will fit into your Progressive machine. I only have Universals, so I cannot test.
Regarding the 327 or similar cases, I would not think a Progressive would be a good choice. The cases would have a tendency to migrate to the outer edge out of the axis of the dies. I foresee several cases getting squashed or having large dents where the die comes down on a case that is not in alignment.
Cheers,
Dave