I did more testing with my DVD ISOs.
Wrapper is superior for playback than KODIs DVD player, the picture is sharper and the colours are more vibrant.
But Himedias own player needs various fixes:
It only plays the main movie, there is no possibility to go to the DVD menu.
Audio selection is buggy.
The languages one can select from often do not play the correct audio stream.
Subtitles are always enabled and have to be turned off with every new playback.
Chapter selection is a few seconds off.
So all in all, DVD playback leaves a lot to be desired.