i still have the stock valves.

i can almost guarantee with a big enough cam and incorrect lash that the supertechs will have the ability to beat the factory valve heads against the seats so hard that they will eventualy dimple and bend, causing lack of compression, and requiring either new valves or at least a valve job.

lighter inconel valves on the intake side are the answer, along with 6mm stainless/inconel exhaust valves. reducing the mass will reduce the momentum and hopefully get better life out of the seats.

the drawback is there will be a ~2 year limit on the head before it needs to be gone through and completely re done.