Well bottom line you cant trust your data to any single source.
Between cloud and flash there is tons of cheap options out there to put a backup of your files on.
Even more so for a business - it is not about the cost of doing something, it is about the cost of not doing something that you really need to look at. If you are simply inconvenienced from the data loss then whatever, if you stand to loose hundreds or thousands of dollars (or hours and hours of valuable time) then that cost is far greater then the $70-100 for a backup drive.