Well, your initial post was a bit vague Pin Head!!!!
The RAF will not appreciate "hour building" instructors as BEagle said. As a FS instructor, you will be training a percentage of the future pilots of the RAF, so they want dedication and continuity. A "stepping stone" attitude is not welcomed. On saying that, it is D of R&S (RAF) that write the policy. CFS check your competency in the air. Having been involved with Tayside Aviation since the beginning of my flying career, I know Mr Fraser (Prime contract holder) is of the same opinion.
Just be wary of what you let people know when you are chatting about FS instructing.
BTW, I have been to OASC! That's how I ended up doing this RAF thing!!!!! Good game, good game