Quick update: I've been running with the Xa Pro 3D Ultras. Mostly around Blue Marsh Lake, a lot of single track, dirt. I got a pair of XA Pro 5's and while they have more cushioning, I immediately started getting blisters on my upper achilles after a couple miles. Never happened with the others.
The cushioning is better on the shoe, though I really didn't mind the XA 3D cushioning.
I'll probably modify the point on the shoe that's rubbing and live with it.