First off, I own and fly a Jabiru aircraft / engine and fully understand the limitations of the engine and the risks of any other aircraft engine - none are perfect. From what I recall during RA-Aus training don't you already sign a waiver as a dangerous activity no matter what aircraft you train in....
I believe the best option for RA-Aus moving forward is to pick a date, lets say 3 months from the initial notification of limitations from CASA and perform a full audit of the RA-Aus membership (10,000 members?)for the following data: Hours flown for period and engine type, then compare reported incident reports and formulate their own data to put an argument forward on failure rates. Repeat for the next three months, that will provide six months of data.
From my observations this topic is driven by politics and not facts, but it has improved safety - how many incidents have there been in the last 8 weeks - not many regarding jabiru engines?
And after heavy handed CASA regulation future incidents will be less likely reported......