But as far as I know you still age while in a coma. So while you may be in a unconscious sleep - it won't do you any good for long term space travel. Then you might as well be awake and look at the scenery along the way.
I guess the bigger problem is that you'd almost certainly need a staff of medical personnel to monitor and manage the sleeping people (whether they're in a medical coma, held at a low temperature to slow everything, etc.) and you're back to the same problem of how they cope with the time and distance.
Can't find any definitive pages but a quick search indicates you're correct - plus there are many disadvantages to being in a long-term coma. Which are avoided by waking up every 3 months but then I guess you're not really avoiding the aging there...
