Current Airtronics are completely compatable with JR.

The 7 channel Hitec receiver is switch selectable to be negative or positive shift. It will work with JR, Airtronics, Futaba, and Hitec.

http://www2.towerhobbies.com/cgi-bin...?&I=LXN524&P=7

Hitec also sells most of their receivers in a positive shift version that is compatible with Airtronics and JR.

All the servos are compatible anyway except the wide blade Futaba's. People just cut the blade off the Futaba's if they need to use one in the other kind of female socket.

There is a old style Airtronics from several years ago that the plugs are wired differently. They are not compatable with any other brand unless they are re-wired.

Enjoy,

Jim