I've had the operation- I had it December 2008 and was very happy with it. Excuse the copy and pasting but here's my experience:
Well for me it's been a loooooooong treatment. I had brace treatment started when I was 14 and am now 18, with another 5 months left to go. And one has to have a further 6 months of specific treatment before they do the op itself.
I had to have my wisdoms wipped out under general first. That was in March. The main operation I stayed in for two nights. By this time it was December, so you get the idea...this isn't as quick a fix as you'd think. I lost a lot of blood and had a scarely low blood pressure, however these were kind of due to me and so aren't regular. At first it's not that bad- the first how I was still knocked out afterwards, then I came round and had almost constant suction due to the blood flow. After that I managed to spit out the blood into a bowl. At this point I couldn't acknowledge the swelling and was in little pain as I was on codeine, paracetamol and patient-controlled morphine, which I used ALOT.
By the next morning I could be assisted by the nurses to the toilet (was still on what they call a 'Step-down' unit) where I saw the swelling. Basically my face has zero shape and my lips were somewhat discoloured. I also couldn't feel anything in my mouth or around my chin or lips, due to the local anaesthetic and nerves affected.
It was only when I was taken off the morphine after around 24 hours that the discomfort set in- my face continued to get bigger for several days and the best description I could give is that I looked like Quagmire off Family Guy. No joke.
I hadn't eaten for 48 hours by the time I got home on day 3 but frankly I didn't feel like it. I was nauseaus and dribbling blood for a further 3 days and could barely stand. I was also constipated due to drugs and couldn't communicate to anyone, hence from day 2 onwards I just sort of cried, though it was more just like eye-leakage due to the lack of facial movement.
It really was just extremely runny liquids for atleast two weeks, because apart from anything else, I couldn't open my mouth wide enough to get food in. I total I lost about 3/4 of a stone and am yet to gain all of it back. For the first week post-op, once the anaesthetic was wearing off I found sleeping through the night difficult and would awake sobbing, so my dad would literally cover my face in ice packs to soothe the pain. And for the first week I couldn't even bare to look at myself in the mirror.
Two and a half months later I had only just begun chewing very gently again, was still not allowed to play sports and couldn't feel half of my chin. I was still not fully able to open my jaw and my gums were taught from where the stitches only fell out maybe 3 weeks ago.
Despite all the this I do not regret having the op, as my teeth are aligned and various side effects of my overbite have now disappeared. However it was a horrible process and involved a lot of crying and discomfort, moreso than pain. The swelling takes a while to come down too.
I'd say think carefully as to whether you really want this doing- I had a rather miserable Christmas due to it and missed 2 weeks of school on top of the holidays, plus tonnes of days for lengthy appointments. Oh and I have to wear loads of red elastic bands to stop my opening too wide.
....
Just an after thought but the operation also CAUSED problems. Since the operation, I've suffered from TMJ which is now being treated with botox, but the effects of that included my jaw partially dislocating, severe pain and clicking.
Give it a really good ponder before making a decision.