I wasn't sure about the DX7, they may have just succumbed to the fact we prefer our 3 pos switch on the left and its probably easier to produce one version, I'm surprised Futaba and JR havent followed suit, it makes no difference for flying planes.

The only other difference that I know if is when you open a new model memory the H version defaults to a helicopter model type and the A version defaults to airplanes.

Also I understand that the radio ships with both parts for the clicker and smooth throttle.