Now it is done. The choice fell on this green chair for under 40 euros, as my wife likes very green stuff and the chair not optically "Granny moderate" looks, but really cool.
Pro:
+ Lightweight
+ No disturbing noises
+ Almost silently through foam cover to the runners
+ Therefore laminate gently
+ Pleasant seating comfort due to high back
+ Stable, ie 88kg man + 6kg baby he holds out easily
- Construction, since the pre-drilled holes were a bit awkward with us not fit, also turned to us a finished threaded through, therefore 1 point deduction
