EGT redline.
The bad thing about the 25 year old that you know, who is earning (well, being paid!) £50K is that he has reached his salary cap, unless he makes Senior Manager level. OK, contracting gives more potential to have ready cash, but then full time has the other benefits too. Sideways moves into tech services etc, get rid of shift work, but the pay does not go up. Where I am, two promotions equate to £4K and then it is behind a desk and that £2K is definitely not worth it! Market rate has removed incremental scales, as you have to treat everybody the same, to be able to attract people with the right qualifications. No other qualifications count towards pay because you do not need them to do your job.
There are big problems within our industry because it is hard work to pass the exams but you will never be a millionaire fixing aeroplanes. I am not halfway through my career yet, but I will be probably working Christmas Day nights for most of the rest of it!