Yes. Merchants that were using Editor 2.0 templates and migrated to the Design Wizard Editor 3.0 templates can request to rollback to the old templates. At the time you complete the Design Wizard, a snapshot of your store is stored. You can contact Customer Care and ask that your store be restored to the snapshot backup at the time of the migration.
Note: Any products you may have added after migrating will not be present when you roll back to the backup copy of your store.