Seems about 50/50 for "use the spray" or install dry.
69 360. I did not deck the block. 74k orig miles. It is really flat as measured with a machinist straight edge. This is going into a dump truck so life will be under 3k RPM. Mr. Gasket shim gaskets say no to any sealer.
What say ye?

 

No sealer. Same goes for almost all head gaskets these days. Especially shim ones. They almost all have a sealer precoated on the gasket itself. Generally can go with manufacturer's recommendations as it is their reputation they are putting on the line.