Known in the USA as "the Fisher-Price microscope." The Fisher Price toy company makes things with very similar color schemes.
The Zeiss Stemi 2000 and the DV4 are not made in Germany they are made by Motic in China as is the Zeiss PrimoStar.
They are indeed very much made of plastic. They do not have prisms but rather a plastic frame with oval shaped mirrors.
Mirrors are brighter than prisms when brand new. But atmospheric oxygen and other corrosive things attack them immediately.
After one or two years they are not brighter than prisms.
I have Wild M5 scopes here at work. Built in the 1960s. In continuous use by students. Still work PERFECTLY.
A Stemi 2000 or a DV4 is better than no microscope. There are many scopes that they would be superior to.
But I would never buy one. I would save my money for a Wild M3,7,8 or a Zeiss SV11