All night flying to short range Europe on the 75 as a junior guy, being tired for 3 straight days. Of course that is similar to West Coast 73 flying, almost all red eyes and late night flying. Much as I don't care for EWR as a location, the 737 flying is some of the best overall, daylight transcons and Carribean beach layovers. Jr base, Jr equipment is some of the best seniority a new guy can get.