The XDM is an excellent choice for a match gun or a carry gun. I just don't feel that putting match grade accuracy and components in a sub compact is necessary or desirable. I also don't feel that cutting a dedicated design gun down to sub compact size is a very useful thing to do. People choose guns like the XDM for shooting matches. People DO NOT usually, if ever, choose sub compacts for shooting matches where accuracy and capacity are important.
Would it make a good sub compact defense gun? Sure, but why? You would never realize the difference but you would pay more for it. Sub compacts just do not achieve the type of accuracy and velocity that would benefit from having "match" components. No benefit other than stroking the owners ego.