With my Service and SC, I didn't notice any difference in accuracy. In fact, I actually shot the SC better for some reason. I know I'm not the only one with these experiences (maybe Todd?). As far as the recoil is concerned, I didn't personally notice much difference, if any at all, in recoil between the two models (these are both 9mm models).
Personally, I don't like the .40 round in general. Therefore, I most certainly did not like it in the XDSC. I shot it, and it has a lot of muzzle flip, IMO. Therefore, the 9mm was much easier to shoot in my experiences.
The 9mm SC is very easy to control and is very pleasant to shoot at the range as well. The XDSC is a very versatile gun being as it comes with the extended magazine making the grip the same length as the service. If they do in fact make the "M" models into a SC, then it will be all that much more versatile. I don't see that happening for quite a while though. Overall, I think the XDSC is a great value. They can be found for a good price.