dead heading:
6 or 7 years ago I was you - wanting to professional pilot and doing my research carefully [although I hadn't heard of PPRuNe back then!]. I got all A's and A*s at GCSE, A's at A level, and graduated from Masters in Aerospace Engineering last July.
Unfortunately whislt I was learning how to design aircraft there were those intent on flying them into skyscrapers, causing the airlines to pull all known fully sponsored cadetships. I'm now working as an engineer and working all the hours I can to save to go the self funded route. I reckon that if I save hard and invest wisely I will be in a position to pay for my training up front in 4 or 5 years. I will then be 27/28 - a full 10 years on from leaving school.
Whilst I'm the last person to deter somebody from attending university, think long and hard about your career goals before you apply. Unless your parents can support you financially [and in which case non of the rest of this really applies] you will have to take out a student loan. Assuming you get the minimum loan, for a 3 or 4 year course you will be borrowing £9 - 12k [I owe Tony and his cronies nearer £17k but my parents were far from well off]. This will cover your rent and tuition fees [currently around £1100 but set to rise to a minumum of £3k a year] and so you will need living costs on top. If you graduate withoout an overdraft you will be doing well.
I reckon that, at a conservative estimate, my 4 years at university cost me around £25k. I'd consider this to be fair value if I wanted to be a professional aerospace engineer, but I don't - I want to be a professional pilot. For another £5k or so I could have gone modular and gained an fATPL. Admittedly, I'd have no guarantee of a job, but I'd be a lot closer to my dream than I am stuck behind my desk at work.
I'm guessing that, like me, you want to do the aero degree as a back up plan for if the piloting doesn't work out and to gain a good alll round knowledge of aircraft and their systems. You will get taught all this via your PPL/CPL/ATPL theoreticals, and if you are determined enough you won't need a back up plan.
Think very very hard what to do when you turn 18.
On one hand you could do the degree and apply for sponsorships, which I intend to do once I have some financial stability. As is mentioned already, 6 years is a long time for the world market to settle down and for the industry to pick up again. You will be more mature than you were at 18, and that theoretical knowledge could go in your favour [well, heres hoping it is for me!!].
On the other hand you could have an fATPL by the time you are 20, and plenty of time to get your first jet job.
Anyway, heres hoping I bump into you at flight school someday soon.
Phil.
P.S. If you do go to uni, check out the University Air Squadron. It's the next stage on from the Air Cadets and they have lots of free flying on offer. A few of my coursemates enrolled as pilots and received £3k a year bursaries, and one of them is now training as an RAF fast jet pilot. The only downside is you have to demonstrate a committment to joining the RAF [My friend did this by signing a 16yr contract]. Senior officers and I agreed this is where I fell down, but fighting wars might be your bag so who knows...