has anyone ever heard of getting a clutch copper coated?theres a clutch shop here that does it for $100.ive heard mixed  thoughts about it .was going to see if any one has done it to a sammy clutch?

What kind of an advantage is the copper supposed to give?

I had one in my old sammy.  They actually have the copper in the clutch material.  They are the same type of clutch they use in tractor pulling.  They grap harder and they don't blow when you slip them hard.  The harder you slip the hotter they get and the better they grab.  I think I got mine with a Preasure Plate and all bearings for $200.  Just make sure you get the spring hub and not a solid hub.  My buddy had the solid hub version in his sammy and it chattered alot.

The best part of the whole thing was when I went to Oriellys to have the flywheel turned.  I set it on the counter and the kid asked me if it was for a manual or and auto.  I picked it back up and went down one spot to the older guy that knew what I wanted.  Maybe they should have some kind of test they have to pass to work there.

how long does it last compared to a standard clutch?

I had it for two years.  It was working great when I sold it.