I just picked up a used S&W model 915 that came with only one magazine. I would like to get a few extras, preferably some 15 round mags if possible. I've read that some S&W mags are interchangeable between certain pistol models but I have no idea which ones will fit the 915. Can anyone offer me some direction regarding this and as well as any advice as to which, if any, brands I should avoid or specifically look for? Are the S&W brand mags best or are there any particular aftermarket brands that work well or better than the factory S&W mags? Thanks!