Former colleague of mine was -10 and had it done, massive success for him. I'd recommend going for an initial consultation - don't think they charge (sure Ultralase didn't) and if you're not suitable they won't attempt to do it.
Did it 10 years ago to correct short-sightedness (prescription was -4.5). Life-changing, after 20 years of glasses and lenses to be free of them for sport (especially in the rain), driving, watching tv etc was just amazing.
Consultation was great, explained the process, assessed suitability...