I've actively been using the Vembu product for backups. It is being used to back up the Hyper-V environment that I have. If the hypervisor has hardware problems, e.g., all the storage dies, you can run up a new Hyper-V server, then restore the VMs onto it. It doesn't take that long. So, you are up and running within several hours of restoring it. Also, you can restore individual files. Therefore, it's a full VM-based image backup as well as a file level backup, if you want to restore the files that way. There is also an option to restore AD users, computers, and contacts, in addition to Exchange databases at the brick level.
I'm mainly working with home-based customers. I don't have any business clients yet.
It's on-premise, not cloud-based at the moment. I'm planning to possibly have replication to an external site since my Internet link is much better now. That will be done in the future. I'll probably replicate to a private cloud somewhere.