I have a SCAR-17, a MR-762, FAL, Hk-91, etc. The SCAR isn't particularly hard recoiling. I certainly never noticed anything. I did notice that it was super handy to carry. I have owned my current one for 8+ years and I have yet to bust an optic. Now I have typically had Nightforce or Acog optics, no junk. My SAR-3 (a Greek HK-91) did manage to bust my Aimpoint M4 (nicely fixed by Aimpoint). I really don't understand all this recoil talk with regard to the SCAR. I will say different people are more recoil sensitive than others, but I feel like I would notice if it was remarkable.

I have been running a Surefire Socom for most of the 3+ K I have through the gun so I guess I am just lucky.