I had set of the " cheap " fabricated valve covers blew out a gasket top end of a run , the bottom of the cover was flat with no provision to hold the gasket in place. I have been running a pair of the Mopar Performance cast covers for years with no problems and they aren't flat on the bottom so the gasket stays in place. I machined all of the ribbing off and all that remains is the Mopar Performance. If I could find a set of fabricated covers that aren't totally flat on the bottom and have an area to hold the gasket in place I would consider getting them for my small block.