I found one of these for sale and am seeking any information. It is not a Legion. The frame is marked Sig Sauer Inc. Exeter - NH and the line below says Frame made in Germany - Sauer.

I see the Legion version is limited to 500 units but what about this one? G 501 is the first part of the serial number.

Is this an uncommon Sig? Thoughts on this pistol?

The P220 was offered in 3 different size configurations. Per Google search ---> "The SIG P220 was shipped in various size configurations, including a full-size model that was originally chambered in 9mm and .45 ACP, and later a shorter-barreled Carry and Compact model."

So are you asking about the Carry OR the Compact?

The Legion version that is limited to 500 units is the "Carry" version in SAO.

The one I’m speaking of is the compact single action only.

I see out of 13 "Compact" sold, only 2 were SAO with the following details:

.45 ACP Sig Sauer P220 Compact 2 Mags Short Grip SAO, Excellent
PRICE: $825.00 MANUFACTURER: Sig Sauer
CONDITION: Used MODEL: P220
SOLD: 9 months ago

P220 CARRY Sig Sauer C3 Compact .45 ACP � SAO 2 Mags Excellent With Box
PRICE: $954.00 MANUFACTURER: Sig Sauer
CONDITION: Used MODEL: P220 CARRY
SOLD: 1 month ago

G 501-XXX places that P220 Compact in the 2009 production time frame.

Don't know if the SAO version is uncommon, but it is DEFINITELY much less common than the DA/SA version.

My thoughts - Well, the p220 Compact is an extremely reliable 'Classic SIG' pistol, so if you want an SAO version of the P220 Compact you should get it, especially if you desire a compact SIG in .45 ACP. I have a P245, which is an earlier 'Made in Germany' DA/SA Compact .45, and for all intents and purposes, it is essentially identical to the P220 Compact. Unfortunately, for me the grip length is simply too short, and I don't shoot my P245 very well. Honestly, at this point I only shoot the P245 at the range, w/ X-Grip Adapters on full size P220 Mags so I can get a proper purchase on the Pistol, and I don't shoot it very often.

For concealed carry purposes, my primary is an HK USPc in .357 SIG, and all of the other compact pistols in my rotation are 9mm anyway, so a compact .45 doesn't serve any purpose for me.

Regarding the manual of arms, nearly all of my rather large pile of SIGs are DA/SA, except for one...A SAO P226 X5 L1. Ultimately, for my use case/needs a SAO Pistol is essentially a Range toy only, and if I get another SAO .45, it's gonna be a Dan Wesson 1911, likely a V-Bob. Regardless though, the P220 Compact is not what I'd consider a range toy, so I'll stick with my X5 for now.

YMMV

Apart from their limited capacity, my P245 and P220 Compact are probably my favorite Sigs. The longer (front to back) yet skinnier grip is perfect for my hands. I like the P229s that I've been carrying lately, by the P220/P245 compact are absolute sweethearts.

Both of mine are DA/SA, but I have a buddy who bought one of the SAO P220 compacts. His was weird in that it wouldn't accept certain factory magazines. The magwell was just too tight for some reason. We ended up trading around some of mine for some of his until he found a complete set that fit his gun. Mine were not so picky and worked with all of them.