I have a SW 1911Sc Commander. Very nice looking gun. It's plunger unstaked itself twice - messing up two matches. Been back to SW after time 2 and has been ok since. One gun isn't a world of data but just a report.
BTW, on the second failure - a friend lent me a beater Taurus 1911 he had in is truck to finish the match. Worked fine. How about that!