[Steve R]

John,
It is a crap shoot for sure. A Good way to provide a little piece of mind is to tear down the new assembly and use a micrometer set
to double check their work, and while your at it, check for cleanliness and make sure it has the parts you paid for, the cam is
degreed, rings are gapped, valve springs don't bind, ect... I did this with the engine I had rebuilt for my van. Glad I did. I paid for good used heads and new valves. I got
cracked heads with old valves, they did not resize the rods. I brought the thing back to them, calmly cross examined the owner
in front of a few customers and his employees. I carried a check out the front door. All the recommendations and BS are no
substitute for using the old noggin.
Remember, drag racers tear their's down regularly. It sounds extreme, but it's not really that big a deal. good luck.
Steven