Chrome steel is probably the seat of choice.  Tungsten is probably used in extreme duty engines, industrial and over the road trucks.  What does your machinist say?  8 bucks more for a valve job isn't much if they are that much better.

John - "The Hoosier Hurricane"

Thanks John.Actually the hi-chrome are cheaper to buy than the Tungsten.I am trying to get a little better informed on my options on redoing these heads.As much as my machinist knows HOW to recondition these heads its up to me on what parts and how much I want to spend.I value the input from members like yourself who have the experience with these motors.