most of our customers already have VMware license and use Veeam backup software to do image-level VM backups of any VMs on their VMware ESXi hosts, so I have a few questions regarding the BE6000. (we are about to start selling these).
a) What license of VMware is included with BE6000?
b) Are the VMs able to be backed-up and restored with Veeam?
C) Can this ESXi host be added to en existing Vmware cluster?
It would be advantageous if this was the case as it would allow an instant restore (or indeed being able to run the VMs or different hardware if there is a server failure of the BE6000). Also would be a cheaper and more fault tolerant design than the 2 x BE6000 solution.
The ESXi license shipped with the BE6000 offers essentially the same functionality as the free VMware vSphere hypervisor. As Navin mentions, this provides sufficient features to virtualize our collaboration applications, but may be limiting for applications such as the one you mention.
If you wish to manage the BE6000 as part of a larger cluster using vCenter, then you can upgrade to the Virtualization Foundation license (R-VMW-UC-FND5-K9) which allows this.