I have both Reflex XTR and AeroFly Pro. I find that the planes fly and behave more realistic in XTR. As mentioned previously, the planes in XTR exhibit stalling more at low speeds. Reflex also mimics windy conditions more accurately than AFP. Although I like the variety of options you can do and more user friendly menus in AFP, I use XTR more for sharpening my skills. I fail to see how anyone can judge how good a sim is against another based only on "3D" physics. There are so much more varibles involved. To me, what matters is how realistic does the sim make me feel. Weather conditions and just generally flying around. I'm sure I am not the only one who bought a simulator program just to do "3D" manuvers. I haven't tried AFPD yet, but would like to.