Recovery model has nothing to do with performance. It's about recoverability.
If you need to be able to restore a DB to point-in-time, you need to be able to restore to point-of-failure, then you need full recovery and log backups. If restoring to the last full backup in the case of a disaster is acceptable, then simple recovery is probably fine.
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