Having done the RMC thing, however luckily for me on an Aviation Cadetship, I agree with Trojan1981 on the SSO option. If you should fail Pilot's course, you do not owe the military any extra time, however through RMC you owe about 2 (or what ever the time is these days) years back.
It is nice to have exposure to the aviation environment prior to joining military, however not actually required. I joined with no experience at all and got through, while one guy who had 500hrs and CPL and other who had 200hrs, failed quite early in the course at Tamworth. In my opinion, get some experience, but remember they train you the way they want, so you need to be able to adapt to their style.
Good luck.
