Of course you like it Schlud; from the outside it's almost a direct copy of yours!
I agree, the finish work appears to be superb and Calmini used nice hardware for the latch and swing pivot.
As for the mounting, I just don't know without seeing up close how the center bracket mounts. I will say that the two frame rail attachements bolt to the very end section of the frame using the factory bumper mounting holes. Those holes were not intended to be weight bearing and are too close together to supply much twist strength (up and down). Also, that part of the frame bends side to side easily. That is why Nissan put the hitch attachment holes at the bottom with one of them being inside the box section. That is also why Nissan provides frame stiffeners with their hitches that help link everything together. Regardless, if the center mounting is strong, then there won't be too much worry with the frame rail attachments. It wouldn't be difficult to beef up the brackets later if you want.
Still, I wonder why Calmini didn't just add a few more inches of steel and put atleast one attachment point inside the box section of the frame and utilize the hitch mounting holes.
Now, as you may be able to see in this picture, my bumper is mounted using two of the hitch holes and one side bumper mount hole because KMA didn't make the insert brackets long enough either. On mine, I added an outer plate and an inner angled pice of steel to reinforce the end of the frame and I attaced them with the hitch mounting hole that is inside the frame rail. I think this is good, but we took things beyond that with Schlud's truck. He had new inserts put on that go all the way inside the box section and attach at all three lower holes and all three side holes.
Anyway, those are my observations. I really like the bumper and that's the one I would buy now if I were looking. I would probably make some alterations though, but that's just me!