> Instead you could take a loan which typically go for 3% for good credit, and keep that 50K in a high interest bank account (2% or more) and pay essentially a few hundred dollars over four years to make sure you have cash available for a true emergency.

A 35K car loan at a net of 1.5% (3% - 2% + marginal tax rate on 2%) will cost over a thousand dollars over 4 years.