Artificial reef and corals?

[btymens]

Hi guys, lately I've been watching a show called "Tanked" about 2 guys in Las Vegas who install saltwater tanks throughout the U.S. They don't use LR or real corals but they use an artificial reef. So my question is, "Is they anyone out there who uses an artificial reef and coral system?" Do you prefer it over the lr etc..? Advantages /disadvantages?