Which is more suitable for very short-sightedness?

[Christabelle]

I have been to see two differrent eye surgeons and they have both given different advice. The first said he would do PRK (it's called ASL in Australia) b/c of my prescription (I'm -7.5 and -8) and sthg about the laser would have to go too deeep.
The 2nd surgeon said that I was a candidate for LASIK, my corneas are within normal range and that LASIK was developped in part for those with higher prescriptions b/c it could handle doing larger areas (or sthg along those lines).
Can anyone tell me whether one method is better than another when it comes down to how blind you are?! I'm thinking that if you''ve created a flap, then you can laser more away whereas with PRK, maybe you can't take off too much of the epithelium?? Any info would be appreciated.