There is undeniably going to be some criticism of BA from many who have not had the chance young enough, or not got through the selection, or for one reason or another would have loved the BA life but didn't get a crack at it. However, some very good points are being made here. As has been alluded to by Wiggy et. al. you are looking at gambling an awfully large part of your life in the hope that things don't end up looking like a LoCo with a hat.
If bidline goes, and if like many of my mates at BA you need to keep working something like 6/3 to make cap each month, then that wait for long haul or command can appear very long indeed. On the other hand, working for BA is "certainly a conversation starter down at the golf club" according to some of the posters in here.
There is no set answer on this IMHO. What makes us happy is different for all. Apples and oranges.