I fly 15 days on, 6 days off for Kalitta on the charter side, and it *IS* rough if you have a wife and kids. (Lost said wife as a direct result of said schedule).
18/12 is what the Charters II guys fly on the 727 and DC-9, a 50% increase in time off at home a month but still only 12 days off after over 2 weeks at work.
7/7 or even 8/6 would be my comfort level with a schedule having a family. If you don't have a family, and like being on the road all the time, the 777 would likely be a great aircraft to fly!
Good luck to those who are applying... They'll be at the Aeroservice Career Fair recruiting in Miami on Jan 23rd, along with a bunch of other operators (all with about the same schedule, unfortunately).
p.s. Is Greg still the CP at SA?