I too work in a boarding school. I went there with no personal experience of boarding (or private education for that matter) and a relative sceptic. I've since learnt that is suits a lot kids incredibly well.
However, 1- it has to be right for your child (and to a lesser degree you) and 2) boarding schools are as diverse in experience as could be imagined.
The other thing to remember is that in the last 20 odd years the majority of boarding schools have become quite open to weekday boarding. In a school of 450 students (14-18yr olds) I'd say only 30 stay in most weekends with most going home on a Saturday lunchtime and coming back Sunday evening. Great if you want to see your kids but if yours is one of the ones "stuck" at school at the weekend it could be a little lonely.
The military boarding thing seems flipping weird to me sometimes. I've got a friend who is a NCO in the Royal Navy who has managed to only spent 18months in the last 20yrs (and that was over 12yrs ago) not based and living in his own house in Portsmouth. His kids board about 2miles from home because if they were day pupils he would not get the subsidy and would have to go to the local comp(which is rubbish) as he couldn't afford the fees. We also had the son of a very senior MOD person boarding at our place who could see his home bedroom window from his boarding school dorm window! Both clearly working the system - but it seems a pretty knackered system.