The problem with ASTM is that external testing is the "modus operandi" in developing standards. The manufacturer may have a vested interest in nominating and using a particular testing entity to obtain a particular result.
Self certification by LSA manufacturers would not seem to be a guarantee of empirical performance data.
So I wouldn't be placing too much confidence in the reported performance characteristics of some of these aircraft, especially with end of flight envelope data.
The question I do have is does CASA make any separate certification determination when registering an aircraft on the VH register v the RA AUS pathway (as was the case with the event aircraft at Stawell). I don't know.