The fact of doing the MCC/JOC with CAE will only give you a good knowledge about RYR Sop's but will not give you any advantage at the time of getting an interview as they told me. IT will help you if you get an invitation because you will feel ready.
RYR used to use Simtech's sim that is why many guys from Simtech got hired, because they were more familia with the sim. But Simtech will not give you anything else than a high quality MCC/JOC as I was also told by many friends.