The advice to use MLS gaskets with aluminum heads...Pffft.
I've ran both Cometic MLS in .060 and .075 thicknesses, Fel Pro Perma Torque and never had a gasket failure with a big block.
I don't know if there would be a difference in an LA or Magnum series engine.
Also, my machinist never decked the block to any specific finish and yet....I've never had a gasket failure.