Hardcore trail and rocks, KRX because you can run 35" tires without breaking a diff or axle... A little underpowered through the straights...
YXZ you can run 32" heavy ply... but that's pushing it, supporting mods suggested...
You can run 30s comfortably.
YXZ is faster in the straights, desert, and on the sand.
If you get the 2019+ year models the rods are turbo ready, 20% stronger than the 16-18. 5psi vs 7.5/8psi+
Many benefits to going 2019+
If you plan to do a full motor build and long travel etc.... Buy yourself the cheapest 2016 (10-12k) and send the short block out built for Boost ($4k) + Turbo kit ($4k) + Long travel ($4k). + ($4k in supporting mods), axle, clutch, diff.... And you will have a pretty solid machine.
Heavy trails, KRX and throw a Supercharger or turbo on it.