I was a 12-hour shift worker for eleven years with an ambulance service here in Canada and I wouldn't of had it any other way..... 3-4 days/nights on and loads of time off. I quite liked being slightly out of sync with the rest of the world in that you could take care of your errands such as grocery shopping and getting your car serviced during off peak times....no crowds, no hassle. The only drawback, if it truly is a drawback, is that your 9-5 friends tend to fall by the wayside and your social circle tends to become other EMTs, Police, Fire, Doctors and Nurses.