Matthew,
I can recommend shrink your SBO-COMMON database. 601GB is a lot. You can run this script:
alter database SBO-COMMON SET RECOVERY SIMPLE; GO /* Shrink the truncated log file to 10MB */ DBCC SHRINKFILE (SBO-COMMON_LOG, 10); GO
About SBO-COMMON backup, you can do it and after restore it if you see that just SBO-COMMON failed. However, if the windows server fails (hard drives, arrays, OS, etc) then you have to reinstall SAP Business One server and a new SBO-COMMON will be created automatically.
Regards,
JC.