Consider that the required instruments will have to be installed by LAME/Level 2 into the RAAus rego aircraft, and probably will need calibration check every two years to be eligible?
Skyecho not useable? because ATC cannot see them?
Now for VH Experimental registered aircraft, any SAAA Member who has completed the latest MPC course, and received CASA authority to work on their own aircraft, can fit their own transponder and any other devices required, to enter controlled airspace in their aircraft,
This will be a big money saving aspect for them?