Thinking outside the box
I think the reason you dont see cheap 300cfm LA based heads is simple... You have to redesign the entire vlavetrain and intake system. The Magnums didnt even come close. They got cheaper to produce, not tremendously better. If one adds good injection and a mild hydraulic roller to an LA, you will get almost identical performance and economy, with a mild increase in emmssions. IMo, mopar has been asleep in the engine department. The new Hemi to me is not state of the art. Simply state of the art for Mopar. The big numbers wouldnt be cheap. Note all the W series packages that require the offset arms and different valve angles and everything tha accompanies those changes. The LS series engines are designed with many of these better features already.