Gary Choka wrote:
I think some things like MS clustering will be impacted by the MAC setting
I think it is mostly the Microsoft Network Load Balancing feature that does some unusual stuff with MAC addresses and needs both setting to Accept.
I agree with other that you could safely leave those at default. In theory, a malicious VM administrator could take advantage of that and launch layer two network attacks, like ARP spoofing and similar, but that might or might not be a risk in your environment.