Verdict
Centauri Carbon is Elegoo's 2024 entry — enclosed, hardened nozzle, $299. K1 is open, brass nozzle stock, $499. The Centauri is wildly aggressive on price; firmware and ecosystem are still maturing.
Buy the Centauri Carbon if: tightest budget for enclosed engineering-filament-ready CoreXY, willing to be on Elegoo's earlier firmware curve, you'll add hardened nozzle naturally.
Buy the K1 if: Klipper community matters, you want a 1+ year track record of community fixes available, accept the open-bed compromise.