Gremlin, I think I learned in a 232. I remember doing loops one day and when I came down an instructor said "I don't think I would do that!" I asked why, he said that plane wasn't stressed to fly upside down. Never got to fly in any of the really neat stuff, but it was the greatest thrill in flying. I do remember making some 'perfect' stall warning landings in the Cessna. Latest though-couple of years ago now-was a Flightstar ultralight that was great! Second only to a sailplane. As for model devices, close may be good enough to accomplish the intended purpose. I have autopilots on almost all my planes for that split second when I become disoriented or lose sight. Try not to out- fly my eyes, but it does happen. Thanks for the explanation of the inertia factor!