Hi Peter-
It's been a decade or so since I've hunted it, but I'll give you a general overview of the area. There are deer throughout 30- from highway 285 all the way to the Brokeoffs. The terrain varies from mesquite draws on the valley floors to steep, rock covered canyons up in the Guadalupes. The mountains have more PJs as you gain elevation. There are deer from top to bottom.
The unit is very remote, but there are lots of roads, and lots of road hunters. We saw several trucks with people riding in the bed with a gun barrel pointed in every direction- be careful.
It gets hunted pretty heavily, but it's not real hard to get away from people, because so many stay on the roads.
You can see a long way up there, so use your glass. I was surprised at all the places we saw deer there- not necessarily where I was expecting to see them. The bucks we saw weren't real heavy antlered, but there are bucks in there. There are also LOTS of coyotes, and lions. Not sure if the predator numbers are like they were when I last hunted it.
Oh yeah, and watch for snakes. They seem to like that country.
You probably can't go wrong in that unit as long as you get out of your truck and spend some time glassing. Good luck.
WH