(Used) Mazda 3 or (New) Ford Fiesta?

I need a new car and have got it down to 2 cars.

I either want to get a Mazda 3 or a Fiesta:

1. The Mazda 3 is 2016, 1.5 TD SKYACTIV-D SE, 5dr, has done 16,000 miles, diesel and is priced at £10,000.

- I really like the car and they seem to have a good reputation, I'd buy this one outright and just keep it until it dies.

2. Using the Ford Privilege scheme I'd get a brand new Fiesta Zetec 1.1ti, petrol, 3 door, for £144 per month with £144 deposit.

- Using the scheme I'm able to swap the car for a new one after a year (but the monthly payments might go up or down by around £10-£20), I'd probably swap it every year for a new one, until my uncle (who provides the Privilege vouchers) passes away.

They both seem like good options to me.
My father has a Fiesta on the Privilege deal which I've driven and think is a nice car but I don't like the idea of PCP. At the same time having a new car every year is quite tempting and £144 seems like quite a low monthly payment for a new car.

If you were in my position what would you go for and why?

I'm generally in favor of buying used cars that are at least two years old. By then the worst of the depreciation is over. When you buy a new car, you lose 20% of the value as soon as you drive it off the lot.

The fiesta deal is a good one .especially as you will get a new car every year .cost of £1728 pa is similar to depreciation. At least you don't have to try to sell it later

I believe Ford owns Mazda so it really doesn't matter. Buy a Honda instead.

Mazda3