How zortrax wants to improve their closed source printer if anybody else opinion is disregarded?
I too like you am forced to take a fact that for now zortrax is very good printer, cel robox comes next but limited built volume 10cm height is making it more a toy than a tool.

Yes your parts printed OK, because they are mechanical parts, rectangular etc. They not figurines with various surfaces that do not print OK from bottom side.
Zortrax does not reply to inquires about what components they use for their printer.
i can buy for example made in china lm8uu bearing for 8$, SKF bearing for 45$ - and I don't think they will work the same do you?