Go For It!
I don't know what negitive stuff you may have heard but flying in the AAC is well worth the effort,
As for joining another arm before going for pilot, it is probably the best bet, might be faster promotion if you go for a remf unit, but you should not overlook the option of either inf or RAC or similiar, this might take slightly longer (only slightly) but will give you an insight into the battlefield that the likes of "sixfoottanker" could only read about in janes manuals. It's also possable that the OC's/CO's of these units will give you more backing in your application, a problem for some of the 'true blue' chaps.
Don't be put off by fools like the aformentioned 'tanker' and get yourself down the the recruiting office before it's too late. (32 for wings)
Hope to see you in the crewroom soon