I purchased G2 about a month ago as well. It has been great for learning and practicing takeoffs & landings and getting used to the mirror effect. In this regard, it is a great investment for beginners!!! I can also see where it would be good for trying out and practicing new manuevers that might be risky to try for the first time with your prized plane. I don't know how realistic it would be simulating torque stalls and that kind of stuff since I'm no where near good enough to try anything like that. It does seem to be very close to real for basics like takeoff, landing, turns, loops & rolls.
But, it's not the same as flying and its not as much fun as flying. If you are already an accomplished pilot, my .02 would be to spend the money on a new plane, I've been told you can never have to many
-Jinks