Thank you very much. I spent another two hours yesterday reading up on that and creating other VMs and Templates, but I was not able yet to attach the Boot disk to a SCSI controller and make it boot. I would really liked to see if this change would bring it on-par with Proxmox (I wonder now what the defaults for Proxmox are), but even then, it would still be much slower than with Hyper-V or XCP-ng. If I find time, I will look into this again.