I looked into Lasik a few years ago as I wanted to get away from using contacts.
The results from my reseach was disquietening.
The best doctors can only claim a 90% success rate and that may involve a second treatment. It's also interesting to note that most operations are done one eye at a time, just in case something goes wrong.
Back to that 90% success rate - what does that mean? It means that after the operation you will have 20/40 or better.
But you have to read the the warnings. While you get corrected vision, your eyesight may be damaged in other ways. Watch out for ghost images, halo's, stars etc. A simple search on google will help you find out how risky this can be despite the claims. IE
http://lasikdisaster.com