Badgerbadger:
It's a fabulous job; of course there are whingers in every industry, but ask the ones in this industry what they'd be doing / earning if they weren't ATCO's....
Shift work is much much better than 9-5, given that we're pretty well protected and only tend to do 2 nightshifts at a time. As somebody mentioned above though, 4am is indeed a hideous time to be awake and feeling like cr@p!!!!! I particularly enjoy never, ever driving in the rush hour, and practically never having to go shopping at a weekend.
Also, don't forget this is a high-status job which gets a whole lot more respect from people than most other jobs you could think of. Add the pay, and the time off, and the fact that it's physically impossible to take your work home with you, and the fact that your decisions have immediate and visible consequences, well... I wish you the very best of luck with it!