I working in a broadcaster compagny, and experience told me that you must backup everything before perform any change, so litle the change are. 1 % risk are too High for me. The UPS protect you, but it Still a gadget that can failled ( it faill me once at work fiew years ago).
I dont think you Will face any problems, but loose 1 night of automatic backup "just in case" are acceptable.
For my case, i use Ext3 for the security of the journaling.