Yeah the S definitely is more firm, as is the 330.I've played the Chrome Soft a lot in the last year and it's my favorite ball. Got a 100 dollar gift card to bridgestone and bought 2 boxes of the B330S and it's a good ball but noticeably firmer around the greens. Chrome soft will check a lot more on those SW shots 20-50 yds out. Distance I think the Chrome Soft is a hair longer but not noticeably longer. I can't speak to the RX bridgestone balls but the B330S is def firmer than Chrome Soft.