I think you can write off the S&W 59 as a magazine option on the Gen 2. The gun hasn't been in production for a long time. The M&P is the S&W model they are using with the Gen 2. Last I heard they were planning on a Beretta 92/96 version, but I'm not sure about the SIG.Yeah I know the M&P doesn't fit the P11. I was talking about the S&W 59. Thanks for the info.