Also as a side note, how will this impact restores? Our ideal use of BESR is to create a system image that we can splat back on to a different box should the main server go down. If we have to create individual images of the hyper v machines I'm assuming we would restore the Host OS, then have to convert the back up images of the VM's to Hyper-V disks and configure Hyper-V to hopefully boot them again? Add's a lot of time to a restore :)
Running backups with BESR installed on the Hyper-V machines, and removing the partition they are stored on from the main backup certainly seems to be working at current without a BSOD.