Friend of mine bought a SIG and it hit low. Since he was clueless I called SIG and they recommended replacing the rear sight with a taller one rather than filing on the front sight to cure the problem. Apparently we are not the only ones to have issues with SIG's POI. SIG has several rear sight options, CDNN happened to have the one my buddy needed. Cheap and quick fix for a proud to own piece of hardware. Seemed to me like old school fit ( tight tolerances, smooth action ). And it will leave a bigger impression than those tupperware items without bending or cracking should you choose to use it as a club.
Enjoy and keep feeding the beast; the sample I used didn't seem fussy about what you fed it.