I don't have an XDm, yet. I had the Service model XD 9mm for a while then traded "up" to the XD Tactical 4.5". I had it in both 9mm and .40 but traded the .40 in since it is no advantage in production competition.
I've had no problem with the slide or anything else. Like a lot of things, until you get your hands on them side by side, it's hard to really appreciate the differences OR, not care about the differences. As soon as I can get the XDm 525, I'll let you know what I think about the two side-by-side.
One thing, Springfield did seed a lot of ranges with rental guns, especially the new 525. Might check with some of your local ranges and do a low cost trial.