It depends on what you are buying imo.
If its cheap and the finance is small and you get a good deal (interest free deal etc) then i think the extra you pay on a new car due to the warranty can be worth it purely in terms of the guarantee of reliability.
My last car was finance and we paid it off in full and then drove it til it started having problems at which point we got a new one outright having saved for it.
I think the biggest issue with finance is it lulls people into buying bigger cars they can't really afford and into the trap of trading it in after just a few years at some considerable cost.
Finance is more expensive, but i do think if you are sensible, keep to what you can realistically can afford and view it as a purchase for the next 10 years and plan forward for your next car then its a goid way to get into longer term reliable car ownership.
Prior to buying my car on finance both DH and I had spent years driving second hand cheap bangers and then having them constantly repaired and they didn't last long before you had to get another.
Dh did work it out when we bought our car that it was cheaper for us in the long run to go down the finance route.
The other thing that i hadnt really considered as part of the equation is the savings you get in fuel efficiency. My last car was far better than my old bangers, and my brand new one is far better than my financed car. So it can pay off that way too.