With most of these tiny companies I don't usually expect an economic moat because it is pretty rare. Mostly, if you find a well run company that is growing you will do well. A good economic moat is a plus but not a necessity.
For INX.V / INXSF, the research report that is out there says that their wider breadth of products and services differentiates them from many of their competitors. Read the Industry Overview and Competition of the following research report (pages 9-10).