G'day VH-AJC,
is it a benefit to have your IREX passed and out of the way prior to to starting the CIR?
In my opinion - most definately. I did my IREX a few months before I started training for MECIR. If you are on any sort of time schedule to complete the rating, you simply don't need the added stress of trying to study for IREX at the same time as coming to grips with sim and in-flight training.