Are you already FI? If so, and spending the the 30K doesn't change your financial situation, go ahead. It wouldn't be a wise financial decision under any circumstances, but if you're in a position to do it and it makes you happy, why not?
If you're not FI, do you have a plan to achieve FIRE? Have you considered the impact of the proposed purchase on your FIRE trajectory? Moving from two solid (almost) paid off cars that have already eaten through much of their depreciation curve to two brand new cars that will begin a new depreciation curve (and which will require more expensive insurance and probably more expensive maintenance) doesn't seem like much of a choice to me. And don't let that 0% interest tag fool you. You're talking about 84 months of debt. The theoretical arguments about the value of a no interest loan don't apply when you're taking on debt for a depreciating asset that you don't need.
If you buy the new cars, in eight years you'll have two used Jeep Compasses that might be worth around $10k (and you'll probably be at the stage where you want to replace them, requiring another loan). If you invest the $360 per month for the next eight years, you might have around $50,000 dollars (assuming 10% growth, which is very possible given the shape of the market right now). If you factor in things like the ability to drop comprehensive insurance, the difference might be even bigger. Unless you have an extremely high income, the opportunity cost of this kind of car loan multiplied several times over your working life can negate a lot of your other efforts in your FIRE journey.
