Mrhinman did a good job of descibing this trail, so I won't repeat what he said. It does sound like he saw more wildlife than we did however, since we saw the hawk, but not much else.
The trail is not too steep, but does climb from ~5155 ft. to ~5650 ft. so it is a decent workout and there is no shade along the trail.
It was neat to see the observatory in the distance as well as the Very Long Baseline Array radio telescope dish, which was also moving while we were there.
After traversing the top of the mountain, this trail descends rather rapidly to intersect with the HQ Trail, but at this point we turned around and headed back to the lodge due to an approaching thunderstorm. (Didn't want to be on the exposed mountaintop with lightning around!)
My wife slipped on some loose rocks on the way down and landed in a cactus, but we still enjoyed the hike very much!