wife has had it via Ultralase, and has had no probs at all. She had Waveform treatment. It's the most expensive at c. £3k. Her eyesight is now perfect.
I think it's important for u to choose the right provider, and be comfortable with ur choice, as there are quite a few providing this now. I wouldn't be influenced solely by cost though.
I'd research the providers and look for forums (fora) with customer feedback. There are many of these if u google - which is what we did.
Ultralase has a sound reputation (as indicated by our research) and it was this and the free aftercare which helped make the decision to go with them.
Hope this helps.