Landshark,
In all honesty, there are very few players who can tell the difference. Even if the club sare set up exactly the same - same specs, shafts, grips, etc. - if a player didn't know wheich was which, he wouldn't be able to tell. Blind tests with pros have proven this to be true.
While I am sure many players claim they can tell the difference, in many cases, it is club design or shaft they are feeling and not head material. From a playability difference, the material makes no difference whatsoever.
Jeff
Jeff Jackson
www.tourgolfproducts.com