Nice catch. I don't see anything that looks abnormal. Just go shoot it.
My Sigs seem to run better with a light coat of white grease on the rails.
If I am shooting a lot on a particular day, I might lock the slide back and put a couple of drops of Rem oil along the rails. Otherwise I field strip after the session and re-grease the rails.
You really do have a great gun and you will like it a lot.