64k allocation unit size for all volume creation tasks.
When creating cluster, volume is 64k automatically formatted. But when you add additional, its 4k.
Jacob Morrison commented
Yes, presently we have to perform a manual task to go back and re-format the CSVs to (the MS recommended) 64k allocation unit size.
Sometimes this manual step is also overlooked which leds to problems later on.
VMM should at least provide the option to automatically format CSVs with a 64k allocation size.