I *love* "Missing Sync" - it's flexible, powerful and easy to use. That said, I have one solitary complaint: upgrading from version 4 to version 5, then from 5 to 5.02 *both* lead to massive duplication of calendar entries on my Treo600. Ultimately, I ended up restoring my calendars from backup and resynching, opting this time to simply overwrite the Palm entries. Next time, I'll know better: sync before upgrading, then after the upgrade is done, simply overwrite the handheld data - don't synchronize. Silly me.