I have the XTR312 with mil-dot
I love it. It is well built, and feels like it's made tough. Optics are real clear, and it seems ot track well so far. Paralax is easily adjusted out.
There are a couple things i dislike about the scope.
1. To range using mildot, you have to put magnification at 11.6, and not max 12x
2. Not a first focal plane reticle
3. Not glass etched reticle
4. Rotating eye piece, wich can make it complicated to mount a buttler creek cap
It's nothing big really, just small annoyances, but it's still a great scope.
I couldn't compare to Nf or Leupy though, as i have not handled one, but for relatively teh same price, you could get the Leupy, wich has a first focal plane reticle, glass etched at that, and the eye piece doesnt rotate.