$1200 for a PC Shorty 45 - with 4 mags is a good deal. Especially if it is in like new condition with the original box.
I have a Shorty 45 MKII. I also have or have had examples of every makers 45 pistol including some Colt custom shop, HK, Springfield, Kimber, Wilson Combat, Nighthawk......et al.
You get the idea. Anyways, the Shorty 45 is THE most accurate 45 pistol I have ever shot. Most accurate handgun I have ever owned. And unlike a lot of those high end 1911s and other 45s I have owned and shot, the Shorty 45 is reliable as death and taxes.
Not one single malfunction in many thousands of rounds. Yes, thousands of rounds - not hundreds.
Mine is currently at a local gunsmith getting new sights installed. Frame wear after all those rounds is minimal. BUT - I keep my rails greased and I regularly change out the dual recoil springs. On aluminum framed big bore pistols, regular preventive maintanance is critical to a long service life.
So, I advise you to buy it, shoot it, love it. In the unlikely event you dont like it, you will likely easily recoup your investment. And probably do it right on this boards classifieds section. Good luck with your decision! Hope this helps. Regards 18DAI