+1 on the S&W over the 10/22 if you are intending this to be a practice carbine. If you want a plinker I see nothing wrong with the 10/22 but take note that the Ruger is pretty much the least cost effective rifle in creating a practice rifle to use in place of an AR-15 or AK. On the other hand, a 10/22 is a phenomenal platform for an Appleseed specific Tactical Training Rifle and for learning the fundamentals.
The only reason I would take the GSG over the Smith was if my personal defensive carbine was of HK ergonomics. So a 93, 91, or MP5 clone would make the GSG-5 more appealing to me as it would factor into training in those weapon systems.
ETA: Save your pennies and hone your crafting skills and you could get one of these: Vector Arms MP5 Style Rifle
I know it's only semi-auto, but you could SBR it later and you'll save on ammo over that boring full auto.