BAE,
Personnally, I think BA is still a better place to be in many respects. I look back at my experience in a major airline and experience in several start-ups and developed lo-co's. For apparently many people working for BA or thinking about working there, the long wait to command is an issue and force draft appears to be a problem. But hopefully this is where the DEP's come in to save the day. Working hard should not be a factor, since everybody else works hard.
But what about pay increases combined with seniority (read lifestyle), decent travel priviledges , SH+LH ops? That, in my view, is the way to survive a long airline career!
Lo-co's careers are overshadowed by a career in a major airline in many ways. Command is usually, and understandably, the only career goal because of money and for some...ego. Lifestyle in lo-co's (better pick of holiday, WE's,better trips...) usually does not improve with seniority and sadly is not given the attention it should have.
Some people seem to have lost perspective of where BA working conditions stand in respect to other carriers around them.
If you go for BA...it probably won't be a bad thing, I guess you can always return to the good ol' lo-co's or charters. I too applied for longhaul with BA, since it is the only way out of a system where lifestyle just does not seem to improve. In my view, BA's seniority system is a developed system, as is the airline, and this gives a chance of getting a lifestyle and paypackage that can improve with seniority.
Good luck !