I have Reflex XTR- have had it for about 6 or 7 years now- and it's great. I haven't checkedthe others lately, but one of the best things about Reflex is that it gives you the ability to adjust the parameters of models, and rename existing ones to your own parameters. This gives you the ability to make your planes snap, lomcevak, and do everything just like the real model. Parameters are thing like weight, power, aileron effectiveness, rudder throw/ effectiveness, cg location. and more. I have a 28% scale Christen eagle, and am very familiar with just how much up, rudder, power, etc is required to make it snap roll, lomcevak, takeoff and land. I was able to adjust one of the Pitts models, renamed to my own name, to fly just about identically. Reflex uses a very good mathematical model for the airplane. It also includes several helicopters.