Promaxx Shocker Series Small Block Heads

First, I have zero experience with small block mopars. I have a 273 2bbl, but I have done nothing with it.
That said, from what I know of Promaxx and the people that own it, I would give their heads a shot. I am somewhat skeptical about the 285 cfm.
I would consult Pittsburg Racer, and Porter racing heads (PRH) for an expert opinion.