I sent my Sprinco Cor Bon unit back to Sprinco this morning. When I get it back it will have a heavier sub-spring installed specifically for 460 Rowland. I believe my next range trip will include my 20, 22 and 24# recoil springs to try with the Sprinco unit. The recoil spring they include doesn't have a rating but it doesn't feel very stiff. Probably a 17#, I dunno. I don't have a way to test the spring for weight.
But I have a suspicion that the Sprinco unit coupled with a heavier recoil spring will make 45 Super feel like 9MM. I'll keep my fingers crossed anyhow.