The main reason why the east German Makrovs are better is the tooling that they used. They're made on WWII Walther Tooling. The pistol is built to tighter tolerances. Less play between the parts. The Soviet produced one are alright too. But the ones that you don't want are the Chicom made makarovs. Those are horrible. Both the military contract and the Norinco made ones.
Here's a list from good to bad.
1) East German - Great

2) Soviet Military - Good

3) Bulgarian Military - Fair

4) Russian Civilian - CRAP!

5) Chinese - WORTHLESS CRAP!