Questions about Provigil, aka modafinil

I have had trouble sleeping my entire life: can’t fall asleep, wake up a lot, then once I get into a good sleep, oversleeping like crazy. I have to be awake at 6am during the school year, a trial that continues to torment me even after 5 years.

Today, my doctor diagnosed me with a circadian rhythm sleep disorder, delayed sleep phase type. For this, he wants me to try Provigil, aka modafinil. He claims this will reset my circadian rhythms so that my body wants to wake and sleep on a regular, acceptable schedule. On one level, it seems like a miracle drug. I can pop awake, feel alert, and be tired by nighttime, according to Doc. No more agonizing extrication from bed, no long hours watching the clock, unable to sleep. Could this be true?

From research I’ve done on the 'net, I do have a few concerns. I’m not going to be awake for 40 hours, as some people claim, am I? I mean, I think that would freak me out, because it cannot be good for the body or the brain. Are there any other side effects worth mentioning? My doc depicted it as having none, but how can that be?

I’d like to have the urge to go to bed when normal people do, sleep a deep, relaxing straight 8 hours, then wake up feeling good. Can Provigil make this possible? Any anecdotal evidence from others who have taken it or prescribed it? Is it the kind of thing you can take for a while and then stop, and maintain a healthy sleep schedule, or is it the kind of thing you have to take for the rest of your life?