I have flown a couple a 7leg day, a couple 6leg days, some 5 leg days, tons of 4 leg days, some 3leg days, and some 2leg days. I can honestly say that I have NEVER ended a day or a trip exhausted. This job is not rocket surgery. Checklist, push, fly, land, checklist, and repeat. I have flown with 20-25 year guys that are 55-59 and have NEVER heard one say he/she has been exhausted. At the end of the 4-5leg days I find myself saying, "Where'd the day go?" It goes very quickly. It's not for everyone, but it's for me because I dont mind work, I enjoy actuallyflying, and I enjoy working with people who want to be at work and enjoy it also.
I found international flying terribly boring. It's as braindead as any flying except for your ears have to be better to understand the way the rest of the world speaks English. -position report, sit for 1hr, postion report, sit for an hour, repeat. Go out after napping 'til noon, walk around in a daze around London, eat some overpriced fish and chips, sleep, come home.
And finally, if ya dont wanna work for your money, dont come here.