The older design had the theaded stud right into the tubing and look much weaker than what is shown in the original post, so hopefully they've improved them.
I have an older pair and was looking at them and comparing and I think I'll rework what I have, or find the correct set location and weld them...don't like the design the more I look at it (for possible problems)...It's good to hear that others have have good luck with the olders though and agree that the locknut is key to have not loosen...guess if there's enough thread, could always double nut them against one another, and some loc-tite, or some sort of safety wire, etc.