With the older FM (Modified Monday, April 01, 2013, 10:10:41 AM) the new model sits static properly, it starts, it taxis, it takes off, it follows its waypoints at correct altitude, it delivers its bombload accurately as long as the speed and alititude are set properly, it flies home to base, it lands perfectly, it taxis to parking, it stops its engines. It will not fire or deliver any missiles under any circumstances, no matter how you set up FMB as instructed.
With the new FM and the new model the tires are sunk in the ground, with the "real" FM it starts up., spins and flips around and blows up. With the "easy" FM it climbs and climbs to outer space regardless of waypoints and altitude settings and will never bomb, or even land. It doesn't deliver any of its missile weapons per the FMB instructions either, under any circumstances.
That's all there is to it.