Stone's a good guy, a good tank, and he really wants a raid. He's done ToC10 twice that I'm aware of- once with my Wednesday pug and once with my sister's, so he has expereince at least through faction champoins. Plus, pally tanks are pretty useful, if I do say so myself
He has a wife and real life commitments, so make it clear that he needs to explicitly communicate "I'm coming" or "I cannot come" even given week. I've had some problems in the past with knowing if he's not coming or if he just forgot to sign up. However, Avrus is his real life friend and an experienced raider, so Avrus will probably help Stone be more communicative. Once he gets in the habbit of explicit communication, I don't expect there will be any problems.