I'm not going to provide any insight here, but just state the obvious. The modular Ness bars have the adjustable angle on the grips section, which could be worth a lot (if your other bars choice is not right for your wrists angle), or it could be a worthless benefit (if your other bars choice fits you just fine).
However, if you're after a set of chrome mini apes, the Ness modulars being to shine a bit more (no pun intended). You cannot get a set of chromed mini-apes for under $500 anywhere else. But if you're after a black set, then once again, the other bars will be your better option from a price point perspective.
Regarding the dimensions, it would be whatever fits you better, although I don't see much of a difference when you have one extra inch of rise, or one extra inch of top width.
As for me, I have looked at these two bars as well for my XR, and was not able to get off the fence no matter how much I looked at them. I might end up going with a custom set in the end. I really like the angles of the KewlMetal bars (see pics below), but KewlMetal is taking a lifetime to make them available, and their price point is still unknown.
This bike was covered in this other thread: https://www.victoryforums.com/showthread.php?t=9478