John, thanks for the response.
The $400 is the difference beween the two options. The purchase price of the MP stamped set, adj. pushrods and rocker shafts is about $400. the adjustable roller kit with shafts, hold downs and pushrods is about $800. I'm just trying to decide if it's worth spending an extra $400 to get the roller rockers. I know they would be a better choice if money were no object, but I'm just not sure if It's justified for my application/build