For years I've heard people say that one WC is as good as the rest but I can't say that's been true in my experience.
gwpercle- thanks for the info on the NOE 160-WC. That may be something to look into.
Interestingly, my RCBS 38-148-WC drops bullets on the heavy side with my alloy and it has proven to be one of the better WC's I've found.
I also agree that driving them a bit faster has shown promise.
The 38 Special is my favorite handgun cartridge and every time I think there's nothing else to learn it proves me wrong.