I've noticed almost all the pocket holsters out there have a flat bottom. The intent, I think, is to insure the gun stays upright.
My pockets aren't flat on the bottom though, they're pointed. As a result, I've been using an uncle mike iwb concealed carry holster tucked in my pocket instead of iwb. This holster is pointed at the business end and settles in pretty securely. Is there any reason I shouldn't do this?