Greatly appreciated after unsuccessfully trying the qnap 5 Gbit.
Only issue that I had was the 2.5gbit link going down in unraid (switch showing that is up).
After re-doing my network setup, removing the network cfg and network rules from the usb, I have now full 2.5gbit using the active backup bonding mode together with my 1gbit Mainboard network.
Let's hope that stays after the reboot