If you had asked me a year ago, I'd have said don't do it. However having just started in the North Sea it's finally worked out for me. But it took 4 years of graft on minimum wage and a billion trial lessons flown to get here. It's a gamble, but coming into it later in life means the odds are stacked against you somewhat.
If you have your IR today, there is a reasonable chance of getting hired, as long as you can pass the selection tests and interview. Lots don't. But things change and the window may close. Timing, luck, determination are important. It's an expensive gamble. Someone on here once said about this, "do you feel lucky".
If today me had the chance to talk to yesterday me about the slog of the last few years, I'd probably say don't do it. Just seen the bit about borrowing to do it, you'll have to think very hard about what happens if you don't get hired, and paying back that money.