In terms of reliability and resale value, the best used Cadillac SUV to buy is either the XT4 or the XT5. Both of these models came with an affordable original price, but have the capability, features, and space that make them winners in the resale market.
The Cadillac Escalade is far too expensive compared to other vehicles and it doesn’t hold the same reliability ratings, while the XT6 is too new to be considered a great second-hand option—there just aren’t that many used ones out there to begin with.