I fly regularly with BA, BD, NW, DL, KL and SN. I find that I have good and bad experiences with all (the good exceeds the bad). It depends who you get on the day and their mood of the day, which itself depends on many other fators. Nevertheless, I think that it is very unprofessional to have a bad day and take it out on the customers. Equally, passengers having a bad day shouldn't take their frustrations out on airline staff. This is the theory. In practice it's different. Being in the business myself I have to confess that these days I often become frustrated at the lack of knowledge check-in staff have about their job. It's probably not their fault but that of poor training standards. Many are part-timers who have been taught the vary basics and no more. The worst tend to be those employed by handling agencies as opposed to those employed directly by the airline. The industry can't keep up with the rollover of staff and training is kept to a minimum.