The card runs under Linux. But I could only get a single one to work. The parallel connection did not work.
Speeds of the disks in the benchmark, was similar to the board controllers.
Manufacturer link with answers to your questions:
https://www.digitus.info/produkte/computer-und-office-zubehoer/computer-zubehoer/io-karten/ds-30104-1/
Greetings