I think it is worth looking at the future and not 20+ years ago (the time when Chevvron and I started out
). Indeed, the whole environment may havce significantly changed in the next ten years with the military side of the house becoming more and more compliant with civil licensing regulations. Furthermore, the whole Air Traffic Management development piece will seriously affect the way we drive aricraft around they sky.
You will find loads of comments about secondary duties etc on previous threads. But answering your question:
The infrastructure is quite similar and the rules are almost identical. They manner in which the rules are interpreted/applied and priorities are allocated can differ somewhat; this is one of the reasons people don't waltz through cross training. Nevertheless, I would say that the vast majority can turn their hand to the opposing profession as the basics are the same. As someone says, it is a matter of unlearning stuff.
I did the RAF route and would not have swapped it. However, I would say that a significant amount of that enjoyment was the variety, opportunity to do lots of different things and the whole 'package' of military life.
Conversely, the civil route offers stability and is far better suited for someone who wants a steady, predictable (ie predictable in how your career will pan out) well paid job.
No one is going to give you the right answer. All I can suggest is that you visit one of the centres (Swanwick/Prestwick), a couple of airfields/aerodromes and/or the training schools (Bournemouth and RAF Shawbury), having a look at both sides of the house. Too often prospective controllers will just have a look at one without so much of a cursory glance at the other; to me this doesn't make sense. Obviously the military route brings additional obligations that you would need to consider, but I think that is outside the scope of this discussion.
Good luck. If you want some military contacts, PM me.