So, basically, you're paying $10k for a brand name and an uglier grille (in my opinion). But...is it important to you to pay that extra $10k? More importantly, WHY is it important to you? Are you just trying to show off? Keep up with the Joneses? Or is your reason legitimate?
In business, it might be valuable to pay extra for a higher-end brand. Why? You don't want to project too much success as a business person because that says to a client "so this is where my dollars are being spent" (Cadillac), but you don't want to appear too cheap (Chevrolet, no matter how loaded the car is...and LTZ model Chevrolets are very nice), so it's best to project an image right in the middle (Buick)...success, but not extravagance.
I've had this discussion both in my office and with people who have been in the real world longer than I have, so there ARE legitimate reasons to purchase the more expensive brand. The question is...is YOUR reason legitimate?
As for me, at this point in my life, I'm perfectly content with the loaded Chevrolet or Ford. Sensible luxury, living smart.