Just testing OMV 6.0.5-2 on a separate testing machine:
Yes, I know its early stages.
smb, ftp, ssh and Rsync work fine. Yay!
External NTFS formatted USB drive works at acceptable speed
The quirks I have found so far:
1.) Dashboard Configuration it not saved. Yellow bar confirmation is missing.
2.) No formatting of disks via GUI. Can only wipe. Must use command line fdisk.
3.) When installing a drive with files, it is not possible to select the existing shares via the gui, unless you know the directory names used.
Found "Browse directories". Silly me.
4.) Can not install any packages via GUI. Getting error message
"Could not resolve 'packages.openmediavault.org')
So far so good. Thanks Volker for the hard work.
PS:. Long time user of OMV starting a long time ago with FreeNAS