For a JK (and I assume JL), I can personally confirm that the Dynatrac uses the same joint and is the same design, just done better (sealed, greaseable, higher quality parts). I'd always go Dynatrack over Ball Joint "Delete" (I put delete in quotes because I can't do it, it's NOT A BALL JOINT DELETE! It's just a ball joint. It's the most BS marketing name ever).
On the Superduty line, they do have a cool feature on the upper where it's dramatically stronger than an OEM stud and essentially impossible to break. That upper is the weak link on the 05+ superduty ball joints.