I recommend bolting on NO ONE's new heads out of the box. I haven't seen anywhere where anyone said to have them "reworked". It is always recommended to take them to a machine shop and have them checked out. Why in the world would you want to bolt them on totally unknown on top of a PILE of money? Take a chance the valve job isn't quite right? Maybe a valve guide or 16 are too tight? Think of how expensive the consequences are if something goes wrong. That's a LOT of money to be out just trying to be cheap and cut corners. Do you want to do the engine build twice?