I don't think weighing up the pro's and con's really works. If the pro's don't outweigh the con's, regardless of what the con's are, then it probably isn't the job for you. I don't really recall any aircrew that had made a measured decision, they just wanted to be RAF aircrew regardless. With enough of those types of people applying, they will always out-succeed anyone who is just there on purely the basis of a pragmatic, reasoned judgement. If there are cons that really matter to you, like time away from home, degree of risk etc, then go for the Airlines.
Having said that, I suppose the major con's all revolve around the operational tempo, large periods of time spent on deployments, the relative instability of family life, the lack of genuine control over your career path, the erosion of benefits etc.