I would agree with L1011 that it will be a bonus to your career. However, the one thing to bear in mind is that your roster will be issued with little if any regard for your desire for time off to attend reserve activities. Certainly in the early part of your career and later depending on seniority. So long as you emphasise that you understand this and that the airline comes first there's no reason why you should not enjoy your endeavour. The moment you start to demand time off to attend training days you become a burden to the operator and then I'm afraid you will find them less tolerant.