That's a brilliant story Calum, got any more?
Ben,
You can apply to any service you want, in any order you want (or all at once.) Please note that the preferred option for many is to apply to the RAF, get rejected, join the FAA and then bitterly complain about the crabs (with a cracking chip on one's shoulder) for the rest of your career.
All the best whichever route you choose.