I am painting up my first space marines. The theme I have decided up is one of religious fervor; when I read about the Black Templar i got to thinking they would be a good army rule base for my guys.

What are the pro's and con's to the Black Templar army list? I don't mind picking a lesser army for fluff reasons, but I don't want an army that doesn't have a fighting chance.

Oh, and can I even use Black Templar rules without actually being the Black Templar?