Scarring is an extremely unlikely eventuality, fortunately. Apparently, the risk of a serious infection following laser eye surgery is lower than the risk of getting a serious eye infection from long term contact lens use. And as saffy202 said, it is possible to end up with better, rather than worse, night vision, after laser eye surgery, if using wavefront technology (although this is not guaranteed - you could pay more for wavefront and still end up with worse night vision, or the same as before, as pupil size is not the only risk factor for this happening). There is also the possibility of problems with the flap created in lasik/intralasik procedures. Again, these are very rare risks, but with a prescription of less than about -6 dioptres, there are alternatives to lasik that don't involve creating a flap in your cornea (generally more painful with a longer healing period, hence being far less popular, but potentially a better idea for some people, particularly anyone who enjoys contact sports, where there is the possibility of the flap becoming dislodged, even years later). There are also other alternatives to laser eye surgery that can free you from wearing contact lenses or glasses, but these carry their own separate risks, so probably aren't a brilliant alternative if you are suitable for laser treatment.
The vast majority of people who have laser eye surgery don't regret it. Many of those who do regret it didn't make themselves properly aware of the risks and complications before going ahead with it, and end up upset that they weren't given more warning when they do end up having problems (despite the fact all the information on laser eye surgery that you could possibly want, good, bad and exceedingly ugly, is freely available on the internet). In fact, I think one of the biggest criticisms of some of the bigger providers of laser eye surgery is their reticence in pointing out what the risks are and how these can actually impact on your life...
I still wouldn't want anyone other than a highly-regarded corneal eye surgeon with a proven track record in successful laser eye surgery, the latest equipment and exceptionally low retreatment rates, touching my eyes, though. And I'd expect said surgeon to have seen me and my test results, and examined my eyes himself, and answered all my questions and concerns thoroughly, at the initial consultation (ie prior to the day of actual treatment), and I'd expect to see him (and I don't mean in passing) at all my after care appointments, too. Not that I'm a broken record or anything!