I am a regular over at the SigForum and I am aware of what post you are talking about.
That was one guy that got a lemon P-220 simple as that. The guy was venting and not really being specific, rather than explain his problem he pretty much just bashed Sig pistols and their customer service.
He was unhappy with the trigger on his NIB P-220, anybody that has bought a new hand gun knows that it takes a little time to beak a trigger into its full potential, his gripes are understood and I can understand somebody being upset if they pay $800 for a new gun and it does not live up to their expectations.
If he took the time and dry fired the gun, testing how heavey the trigger was he would not have had to go through all this trouble. I dont know about you but I have a routine I go through before I purchase a gun, testing the trigger pull is defineatly one of them. That was a problem easiy avoided.
OK, enough on that post.
As far as rust goes, I have had 4 Sigs over the years and can honestly tell you I have never seen so much as a spec of rust yet. There has been times where they have sat in my safe for months and still, no rust.
If you take care of your guns and clean them after shooting them I dont see how you could have any problems. Lets face it, Sigs did not get their reputation by making rusty guns that are going to crack on you. Sure, it might happen but that about 2%, not really enough to get up in arms about.
JAson