Adjustable sights, beefy magwell grips, Threaded barrel and a rail. This is cheaper then I have found the plain Jane model for lately. I'd pick one up myself if I had the cash to spend on it
http://www.cdnnsports.com/gsg-1911-target-22lr-5-rail-target-grips-1-10.html#.VaKHSPlViko
http://www.cdnnsports.com/gsg-1911-target-22lr-5-rail-target-grips-1-10.html#.VaKHSPlViko