DEP here, LHS LoCo to LH.
A lot of good feedback on this thread, so I thought I'd throw in my two pence on a couple of points that have not been raised.
The first is that LH can be rather difference depending on your fleet. The most senior FO on the 747 will look at the blind line of the most junior FO on the 380 with amazement. So even though LH is still a much better gig than SH (if you can manage the sleep), your lifestyle and contentment may vary somewhat based on your fleet.
My second point is that a switch from LHS to RHS, even if it can be a bit frustrating at times, brings a significant reduction in stress. I can see why the guys who go EZY to BA SH regret their decision at times, as their hours an stress levels will be comparable. But for yours truly, going from the stress of 5 days in a row of bad weather, dodgy Greek islands, disruptive passengers and very junior FOs, to flying ILS to ILS four or five times a month with very experienced skippers, has been very enjoyable. And I, for one, am less tired than I was with the LoCo.
In general, I find people to be very pleasant to work with at BA. Training was very relaxed and 90 percent of the skippers seem to recognise I know a thing or two about flying. I work 3 out of 4 weekends though and going from a fixed roster to the vagaries of being junior on a bidding system has impacted family life to an extent. On the plus side, I am a lot less stressed and tired. I enjoy looking after the kids more than the last two years in the previous job (I had become pretty grumpy). Even the missus thinks I'm slightly more likeable than before.
One last point, which has been mentioned a couple of times on the thread, is that no one knows what the future holds. Alex Cruz might tighten the screw so much that the likes of five year fleet freezes might become 6, 7 or more. And heaven knows what else. But then no one knows what the future holds for any airline, and my ex-colleagues tell me on a regular basis that things are getting worse at my old outfit. You could draw lines to chart the decline of terms and conditions at all airlines and they would be more or less parallel. But BA would be one of the top lines, which makes me think I made the right choice.