Wow, I won't be buying a Sig...
but here's my story with Ruger.
I was shooting my SP101 snubnose with some super hot Double Tap Ammo, 1605fps, 710ft/lb. Along with assorted other hi-power loads.
Now let me remind you Ruger has no implied warranty.
I cracked the forcing cone/barrel, so I just sent it in, didn't even have to call. The service info said to remove all items you might want, so I sent the gun in a crappy old hard case I didn't want anymore. I received a notice a week after I shipped it that confirmed Ruger's receipt of my gun. Then a few days later the UPS man comes to my door with a package from Ruger....in it is my crappy case they sent back for free. LOL.
About the same time, a CS rep from Ruger calls to tell me my gun is being fixed and it will be back in my hands less than a month from when I shipped it out. No charge.
While I haven't gotten my gun back yet, I am extremely pleased with their CS. I was already thinking about buying an SR9c but now I will for sure.
This was exactly what I was feeling when I heard Sig was going to ship me a new pistol (only I wasn't told to take parts off). I was happy as a clam until I got the new gun and found out it was the same as what I sent in. Imagine if your SP101 came back with the cheapest sights possible, a MIM trigger, plastic parts where there used to be steel, cheaper grips, etc.
Note: I have nothing but good luck with Ruger and I hope (expect) them to treat you right.