If the option is 25k for a car I "can't repair" in 5 years or 50k for a car I can - I'll take the 25k one, if I can get the warranty to cover those 5 years, all else being equal.

Everything is "repairable" it's just a matter of is it worth repairing. Maybe rebuilding the car every 5-10 years isn't that bad of a model.