Cloud backup is widely used for offsite data backup. Traditionally, you would backup your data to an external disk or tape and ship the disk/tape to an offsite location, which is hard and costs a lot of money. Offsite backup is the only safe backup solution that can survive a major disaster such as fire, earthquake, flood, or virus, etc.
Cloud/offsite backup is usually not designed for system backup. If you system fails, you can easily restore your system using the recovery CD, or you can install a new system. Once your system is recovered, you can install DriveHQ Online Backup or DriveHQ FileManager to restore data.
DriveHQ Online Backup 5.0 can run as a Windows/NT service. It can backup your computer/server even if nobody is logged on.
>>> Is there a good way to get a test machine and run disastor recovery tests?
As mentioned above, you probably only need to verify your data integrity. You can backup your data, then restore/download the data and see if there is any problem.