Bank loan isn't necessarily always the best way, it depends on what you want to do with the car. If you want to change your car fairly frequently, then a lease/purchase scheme can benefit you by having a car with a very good residual value so that you essentially only keep the car for 2/3 years and then have a final balloon payment that allows you to either
1) buy the car at the end of the term
2) hand it back and walk away (essentially you've rented it)
3) if the car value is higher than the final figure, use that as a deposit for something new
This also lowers the monthly payment for more expensive cars, however as you are all already aware the APR will be lower with a bank loan but you'll be paying it back for a good four/five years most likely.
Works well for cars that are very expensive; take a porsche boxster S - sticker price will probably be (for example) £35000 (try getting a bank loan for that!) but residual price will be (again, guessing) £20000 after 3 years, so in theory you're only financing £15000 because the final payment is large. After three years, hand it back and get something new.
It's horses for courses, but i'm a regular car switcher and prefer not to have the negative equity of a bank loan - it's too tempting to take the loan over a long term and not cover the depreciation of car in favour of lowering the monthly payments.
