I own a Petrof 115 from 1988. It has a typical Petrof romantic sound with a heavy action. When disassembled, the lack of quality control is visible. The hidden part of piano keys are far from smooth; you can even see splinters. On the other hand, it is a sturdy piano which hold a tune extremely well and for more than 30 years plays without any repair.
These pianos were designed to survive children bashing in public music schools. They were mass produced, and as Mr. Gallasini said, they had lacked uniformity.
I have been very critical to Petrofs at first. As a child I disliked its heavy action. I rather played our old baby grand with a viennese action that the Petrof. As and adult I saw the guts... But when searching for my grand, I came across some uprights. I must confess, even if I am not very fond of Petrof romantic sound, my Petrof was superior to other old uprights. So I have slightly changed my opinion.
If you really like Petrof sound and the piano is well preserved, I would consider to try it. My only concern is the hight (100 cm). If it would be 125+ cm, I would probably not hesitate. They should be of better quality.
I fairly hope, that helps at least a little bit,
Scholze Some additional information about Petrof history can be found on official webpages and little tidbits in my comment here.