Frog, as far as I'm aware, the medical requirement for all three services are the same for Aircrew selection. Eye sight has to be 20/20 (or whatever the new name for it is) on the selection medical but once qualified, as long as you can remember the letters on the eyesight test chart and know which end of the tube to pish in, thats good enough. Laser surgery is still discouraged but I'm not sure how a serving aircrew type with this procedure would be classed on annual aircrew medical.
If you are thinking of going for AAC 'flight crew' (never heard us called that before!!), I would seek professional advice from a SAM (Specialist in Aviation Medicine - Flying Doc) if you have or are thinking of having laser corrective surgery. I believe the issue regarding contact lenses is a bit more relaxed now but, again you will need to seek proper advice.