Whether it's worth it depends largely on your aims and ambitions. If all you want to do is be in the RAF, then it might well be, and you aren't that bothered about rank or trade. If you're thinking it could be a stepping stone, as camelspyder noted, it could go either way, and OASC will expect more of you as an ex-ranker given the exposure you'll have had. That said, I personally know of at least 3 individuals who joined as NCO aircrew and went on to get a commission, including one as a pilot. So it can be done, but it's not necessarily easy.
Oh and unless there are genuinely no vacancies in the Branch / Trade you're interested in, or you are outside the criteria, just bear in mind that OASC will try to steer you down certain routes to meet quotas - they tried to push me into Med Spt to meet such a quota. So when they say it's impossible or suck their teeth and say oooh tricky like a plumber you've just called on Christmas Day to fix the boiler, bear that in mind and follow your heart and instincts and go for it anyway. I'd be doing medical admin if I'd listened to them when I went through!