Background: My first non-issue firearm was a Steyr M9-A1 circa Christmas, 2007. I loved the handgun, though I did have the old "short" magazine spring issue, and Jeff was kind enough to send me a replacement extractor upgrade. Later, when SAI dropped the M9 line from the market, I ditched the gun. I don't keep firearms that aren't supported, or become increasingly tough to find holsters/magazines etc. Fast forward six years. I currently own two Walther PPQ's in 9mm. One of the finest handguns I've ever owned, and without question the finest trigger. However, I have always liked Steyrs and I have a couple of things which are nagging at me. 1) The Steyr can take a quality RMR install easily/cheaply. The PPQ can not. 2) The PPQ is a great gun, but being a slender guy, the pistol grip is a little long. This may be rectified in the future with a compact model, but this isn't a sure thing. So. I talked to a Steyr owner on another forum when I saw his RMR'ed M9. My ideal plan would be to acquire both an S9-A1, and a C9-A1...provided the slides are interchangeable, as well as magazines. Is this possible? Furthermore, what's the "newest" S9-A1 model and how can I locate it online or in-store? I know the C9-A1 is relatively recent, so I don't expect too many variations. (Obviously, all of this is likely going to be hold over for a few months until the political panic dies down...) So, convince me.