I had run across info some time ago on the net regarding simson but I can't find it now. From what I remember, for a certain period these guns could have been made by Simson, Sauer or Merkel as they were all made in the same factory. The examples on Tradeex are the bottom line guns.
Here is a blurb that I had on file.
For Suhl guns, the short version is "same gun, same design, same workers, same factory, different label".
The long version comes out at book length or longer.
The biggest issue is whether the gun was stamped as Q1 or export quality. If it was, with proper care it will outlive you and me both.
Hi, the Quality stamps are normally found on one of the bbl lugs.
Here's a quick run down on the Quality Marks found on DDR Guns:
Q1 (since the early 60s) and “S” (until 1960) = superior quality over the average level of the world market
1 = good quality on the average level of the world market
2 = sufficient quality; adequate but below world market level
These marks are found only on DDR (East German) guns. Guns that are pre-war or West German won't have these marks.