I was wanting a new Glock 17 or 19 but I figured why bother. I would have been more than happy with a gun that can hold 17 rounds of 9mm ammo but since the magazine ban, you have the choice between 10 rounds of 9mm, .357 SIG, .40 and .45 in comparibly sized packages. Why would anyone choose 10 rounds of 9mm over 10 rounds of .40 or better? I know the price of 9mm ammo is slightly cheaper than .40 ammo, but is that the only reason?