Congrats on your new ride! The Warlock is a good looking truck. Reminds me of the 2017 Rebel I used to own.
I never buy extended warranties, so I'm not much help there. I Just wanted to give you some unsolicited advice. Keep in mind that things can get tricky if/when you go to order parts or accessories for it. The Warlock is in essence a 4th gen Ram 1500. It shares many parts with the 4th gen Rebels, but most of the parts are shared with the Big Horn. You'll have better luck if you specify a 2018 Big Horn or Rebel, depending on the part or accessory you are buying.