I went for the PCP option when i had my E93 3 series 325i convertible. Was paying £500 a month ..with a 10k a year mileage allowance. Had to say BMW was quite flexible even though i was way over the annual mileage allowance. Had the car for a year and thought to myself..that car is not(never) mine even though i have traded my A4 in for £3k on top of the £6k i have paid over the one year of ownership. And it cost me £500 just to replace the front 2 runflat tyres My work circumstances changed so i decided it's no longer viable to keep paying £500 a month to finance the car.
It works well for people who likes to be seen in a new BMW model every few years or like srobien said you could buy the car outright at the end of the 3 yrs and pay a lump sum balloon payment and keep the car or give it back and use the car as a deposit to refinance a new model. IMO it's another form of car leasing. I did the maths and it work out even if i decide to pay the balloon payment and keep the car at the end of the 3yrs, i would have paid more than £6k in interest above the initial advertised price of the car. At least the Zed is mine and not Nissan's. It's the first time i have taken out a PCP deal and i don't think i will do it again in the future..think i prefer to take out a car loan when i get my M3 someday.