There is a thread in the armed forces forum about nursing in the RAF, I'll find the link.
edit: here you are:
http://www.thestudentroom.co.uk/showthread.php?t=1724381As a military student, you are employed by the army/navy/RAF and they pay all tuition fees. Because of this they expect you to serve a minimum of four years in the forces post qualification to pay back their investment.
Basically, you need to think about what you want from your university experience. If you want to live the student life for your three years, going out and having fun with as much freedom as possible then going to uni as a civilian may be best for you. If you want to be financially secure for your three years at uni and aren't too bothered about having the full student experience then maybe joining the military prior to uni would be better.
As a military student you're subject to military discipline, you have to attend lectures at all times (civvy students are supposed to but can get away with missing some) and when other students may have one lecture in the morning then the rest of the day off you might be expected to undertake further activities or study. For this though the military pay you a salary, compared to scraping an existence as a student nurse on a bursary. It's competitive to get into, especially seeing all the documentaries about at the moment showing CCAST and MERT with the troops out in Afghanistan.