A military (flying) background is a great advantage - once you have accrued enough experience to be valuable. That'll take you around 8-10 years, on average, after which you must either have a retirement option (which will carry some financial benefits) or you may resign (which may not). The amount of re-qualifying you will have to undertake will depend on your Service experience; obviously an ex-C17 pilot will need less retraining than an AH-64 pilot, assumimg the aim is to fly airliners. No doubt BEagle will chip in with the latest exemptions available to Service pilots.
Many, if not most, military pilots move on to civilian aviation at the end of their engagement. That is unlikely to change anytime soon, though the overall numbers are decreasing with the contraction of the Services generally.
Scroggs