The barrels have fluid steel chambers with damascus tubes screwed in and fluid steel muzzle piece. This is Pieper's major contribution to the sxs development, though he in fact held many patents.
Yes, Pieper produced some unique patterns. Pieper ran his own barrel making shop which he named, "The Brazil Works".
For the Belgians, Twist, Laminated and Damascus were all produced using the same forge welding methods. The difference for them was in the billet assembly. Technically this may not be true of all countries.
It is an interesting example of the Pieper Diana as it evolved over time. The Diana and Modified Diana came in many grades. I have seen simple twist to Bernard type patterns on them. I have heard of 1 than had Pieper's name woven into the damascus.
Would I buy it? If I did not already own a Diana, then yes. I would not consider it high volume gun nor meant for heavy loads.
I would keep the pressures to 7,000 or less.
Pete
