I got both the round-cut Mika holster and square-cut and, depending on pant pocket, use either one.
I also took some of my pants where the pocket was a bit large and used my wife's sewing machine to sew some rows of stitching after carefully marking with a ball point pen, the material of the inner pocket (pants off, of course). Where there was a wide enough gap leftover, I just sewed back and forth to create a strong separation and then sewed up in a semi-circle to the rearward connection of the (right) pocket at the top to keep lint and other things out of the narrow space created behind the Mika Holster.
That has worked extremely well at keeping the holster in perfect alignment in my pant pocket. It has also helped with retaining the holster inside the pocket, not that the holster ever came out, because it didn't. I could do cartwheels and handstands now (if my back were better) with large pockets and the gun and the holster are there to stay in my pants that have large, LOOSE, pockets in the front.