Warning: Since the DB is in simple recovery, you can take file and file group backups at different times, but you won't be able to restore them (unless all but one are read only).
Stick to full backups unless you like surprises when it comes to restore.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability