RE: NM unit 15
Unit 15 is in the western part of the state near Quemado. It's a fairly large unit and goes from Hwy 60 south toward Reserve and from the AZ border east toward Pietown/Magdalina. Most of the time I hunt elk in the area around Quemado lake so I haven't really checked out the rest of the unit much.
I don't know anything about 24, I never go that far south, at least not yet.
Good luck in your hunt.