[I bought rock from the marine center a while ago. It had little to ok coralline but it had NO bad things like aptasia, mantis shrimp, hair algea, flatworms exc. In other words sometimes less life is better in that you put in what you want or atleast have more control and not spend countless hours and money eradicating a hitchhiker problem. In this hobby good things happen slowly and if you speed things up you usually pay a price somewhere. Coralline and bacteria is all you really need on liverock. The best rock is from an established hobbiest aquarium look there first JMHO]
It is only really good quality LR I have ever seen in the DFW area, unless you special order.]