I bought the original real flight and the RFG2. IMO the planes fly fairly realistic. I'm not not talking 3D, just basic flying. You can learn without a sim, but I remember getting frustrated trying to find time when an instructor could help, only to have the weather cancel your day.

I originally used the sim to learn how to use rudder. making coordinated turns for hours, and make left and right hand landing approaches. I did this so much that I was moving the sticks without even thinking about it. They are worth the money me.