You dont actually know he is a bullshitter. He looks like a man of his word and didnt care about the people he killed, His family were pretty evil to him.
I don't think you can call a multiple murderer (if he was one) a man of his word. Claiming he commited loads of murders for Roy when supposedly he only met him once to buy a gun ( Montiglio hasn't mentioned him as far as i know ). Not to mention his claiming to be involved in Hoffas death i think it's safe to say he was at least partly bullshitting.
