I myself would go with the M&P .40FS that way for around $80 you can get a .357sig barrel and shoot .357Sig. Now another $80 and a new magazine and you can shoot the cheaper 9mm! So for the price your looking at around $500 you can get the M&P, a quality weapon, and for a meer couple hundred more you can have 3 different guns! That was one of my reasons why I added the .40FS to my collection. If you go this way, I guarantee that you won't regret it in ANY way! Now the Sig is a wonderful weapon no doubt, but 3 guns in one. Can't beat that.