c_jephcott,
I'm in your exact same position (even age!). While I'm not un the UK, and training is as far as I know still cheaper here, I've come to the conclusion that taking out a big-a55 loan like that is insane.
I've decided after University I'm going to go with modular training, allowing me to work at the same time. Well actually I'm only in 3rd year, but almost the same as you. I'm going to do my PPL during this summer break, then continue with my training when I'm done school the next year.
Just imagine how much, especially at our age, you would be blowing your life away by getting a 70,000 (£ even!!) loan!
You are basically writing off 10+ years of your life to paying debt. Having no life whatsoever outside of your flying job because you can't afford to do anything, but sit in your house and eat baked beans. Personally I know I have other goals and things in life I want to do besides my flying job. If I was giving up my entire paycheque to debt, none of that is going to happen.
For me, and I imagine for most people (unless you are rich, the exceptions) the choice is clear, it is better to work full time while you train. While it will take longer, I think it is well worth it.
Anyway, just a little insight into my thinking, good luck.
ps. Not even considering the situation where you have all that debt and can't find any flying job! methinks life would be looking pretty dim then...
pps. come to Canada with a CPL and get some bush flying in! If you truly want to experience flying before you step into a jet office...