SIG 1911 are 1911's not "SIG's", to my way of thinking.
The first of the series, the P220, originally imported by Browning with Brownings name on it in both 9mm and 45ACP, was a unique gun. The slide was made of a sheet metal stamping, welded up with an insert for the breech. The barrels were very accurate and well fitted to the slide. The barrel lockup was a block of steel as part of the barrel that engaged deeply all the front edge of the ejection port, not a series of groves and lands on the barrel top with very little engagement in their mates in the slide top. Loose breech is a common semi-auto malady and SIG P220 series guns is one of the few guns that has virtually zero out of the box. What loose breech allows is the barrel to get a run on the slide and the locking lugs on the barrel will get so beat up the gun will no longer lock closed correctly. Unless the barrel hood on a 1911 is fitted (usually requires welding on the hood and filing or machining for a close fit) most 1911 suffer loose breech or at least the beginnings of it.
The look and feel of the guns were exceptional as was the fit and finish. The P220 is a single column gun with a grip I can get my smallish hands around. The mags are well made, all steel and feed perfectly. The weight is about perfect and lighter than a 1911 (better for me).
While I like the 1911's and have a couple my self, the Sig P220 series is a modern design, using modern processes, that ends up with a better gun , design wise, in my judgement.
Now, the recent ones no longer have the stamped and welded up slide and are no longer made in Austria. Are they as good as the earlier version? I don't know and don't care as my two SIGS are both earlier version and I love them dearly. It boggles my mind that anyone would want to sell an earlier one.
Today they are very expensive and they were when I started buying guns in the mid 1980's. When most centerfire semi-autos were under $500, the P220's were $750 and up. I found my 45ACP P220 at a gun show used in the mid 1990's. It had one magazine of ammo shot through it and the price was very right. The P225 I got when I had a FFL on a distributor sale for a song a few years later. In those days those were the only ways I could afford a SIG. Glad I got them!!!
LDBennett