I won't bore you all with pics of every difference between the contacts, but below show the key differences which ultimately made the first set useless.
(Genuine contacts are on the left)
As you can see, the taper on the pin is very different, as is the back taper on the clutch set. This meant that the
throw increased due to the increased distance needed to make contact with the copper tube. Unless I had a poorly machined version, I fail to see how any of the clones of this type would ever work without extensive filing or replacement
coils. The rest of the
mod is very well machined by the way.
Today it has worked flawlessly.