There's minimal difference in operation between the first generation XDM and the older OSP model. Other than the integration of the optic system itself, tall sights, and redesigned slide serrations. In my OSP, however, I did end up going with a PRP stainless steel guide rod to give it a little more weight up front. Combined with the weight of the viridian, I feel that the slide tracks a bit flatter in recoil.
Pros for the Elite OSP on the other hand: While I haven't gotten it to the range yet (tomorrow hopefully), it has a much improved trigger in bother take-up and reset. The Elite also has the wider serrations for easier slide manipulation, not that it was all that difficult to begin with. Further, the fact that it comes factory with a magwell was a plus in my eyes. The negatives that I have are nitpicking and aren't necessarily the same for everyone: On the Elite model, with a full two-handed grip, the slide stop/release rubs the meat of my thumb to the point of irritation within 5 minutes of dry-firing. I would've preferred the ambi control to mimic the old design. Second, I think there should be an OSP model option with a front fiber optic sight. Nitpicking again, I almost wanted Springfield to update the frame's grip texture to be somewhere in line with the mod2 or hellcat grips just to make it different. Lastly all xdm models should come from factory with a rolled striker retainer pin since it's been a known potential issue for some time.
All in all, I'm sticking with the XDM's and Springfield as my go to. They feel better in my hands than most other manufacturers, and the grip safeties are a non-issue for me. I'm ready to see what comes in the next iteration or to see if Springfield will switch things up similarly to the most recent Walther release.
