Nice mod to the magazine ridge Red Cardinal & Iggy, think I'll have to try this myself for both my 457 and CS45 mags.

Just an FYI, I recently tried purchasing some CS45 mags from Midway but they were all factory defects without the proper guide stamp on both sides. I returned them for more but every mag they sent me was defective. Looks like S&W dumped these bad mags on their retailers, be sure to check yours out before the exchange limit expires.