tegemu is right, an IWB mag pouch is just not as comfortable as a holster. With an IWB holster, there is quite a bit of length below the belt line and the pressure of the belt is distributed across the entire width of the pistol and holster. With a mag-pouch worn IWB, the pressure of the belt is concentrated across approximately one inch of magazine width pressing it into your side. And to achevie an adequate grip IWB, the mag needs to be seated so that the base of the mag is about even with the bottom edge of the belt which pushes the bottom of the mag into you. While these problems may be alleviated somewhat with a widely spaced IWB double mag-pouch, as stated it really wouldn't be much more concealable than an OWB. With most OWB mag-pouches there is only about 1/2 inch of pouch below the belt-line.