Powdered metal seats, {Durabond Killer B for example) are more common, at least more machinist friendly than beryllium copper/bronze. It's all just money but for most people, the Ferrea hollow stem valves are better return on the dollar. Unless you have the heads and are willing to cam to support the high rpm, I would think that taking the titanium valve money and spending it on more cubic inches makes more sense, especially in a mopar situation. S/F...Ken M