Why should you use Quick Migration if Live Migration provides more uptime ?
Live Migration can place a heavy burden on networking resources to accomplish the VM move.
Since there is a heavy load, only one vm can migrate at a time using Live Migration, and if the load are really heavy, the migration might fail.
Quick Migration saves the mamory state of VMS to be moved, and are capable of moving multiple VMs from one node to another at the same time. The VMs are 'frozen', and might not be acceptable for some organizations, so be sure to select the right migration.