The advantage of a personal loan to me was owning the car from the start, so any job loss etc I'm free to sell the car, pay off the loan & keep the remaining money to buy an old banger to keep me mobile (I don't like the idea of just handing a car back that I've paid a large chunk for & not having anything to show for it, but that's just a personal viewpoint). Lower monthly costs by financing elsewhere 3.5% rather than the (at that time) 11% apr on Audi pcp. No mileage restrictions (I exceed 25k miles annually). I'd suggest the rather boring route of sitting down once you have all the figures for the various options PCP, lease & personal loan etc & work out which looks the most suitable option for your situation.
I have to agree with Rich on this one, a personal loan definitely gives you more options and the important thing is you have something to show for your money and do what you want with it. Plus why pay 6-7% APR on a PCP when you can get a personal loan 50% cheaper?
I don't agree with putting large deposits down on cars either, so for me, if I was financing a car through PCP (which I would never do anyway) I would put the bare minimum down and take it from there. It's a depreciating asset after all.
Putting larger deposits down on appreciating assets like property makes sense financially especially as you will be in it for the long haul and the larger deposit gets you better mortgage rates which can save you thousands over the course of 25 years.