Result and general impression …
The Icy Dock ToughArmor MB839SP-B removable frame fulfills all promises of the manufacturer!
With about 69 Euro it is not necessarily cheap, but it does without the SATA interface of the motherboard, because the otherwise often unused PCIe 1x slot is used for this.
The workmanship is first-class except for a somewhat unclean solder joint on our test sample and the installation is plug and play. In none of our systems we had to install a driver, the MB839SP-B was recognized immediately without any problems.