I'm huge fan of projection, I prefer it over MysAds every-time.
Why exactly?
I see it as a useful scouting tool at best, and something that can be replicated by driving near the area and using Perception.
Need to find someone and you have a material link? Ritual casting with a projecting mage can speed up the location time.
Need to tail a paranoid target? Astral projection.
Need to talk to someone half the world away and don't want to leave a datatrail? Astral projection.
Need that obscure piece of occult info that only spirits know? Astral projection.
Need to know exactly where wards are so your christmas tree mystic adept or physical adept or dual natured partner doesn't debuff/KO/disrupt/alert? Astral projection.
Good old fashioned over watch?
Lots of uses for projection that perception just can't do, or is second fiddle to....