To be honest, I think backup devices are a leftover from tape days (as in when backups were done to tape directly). There's little use I see for them with disk files and they give an extra level of obfuscation (where exactly are my backups going).
Backups to disk, no devices, each backup to its own file with a timestamp as part of the file name
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