The MySQLi Server behaviors singularly replaces Adobe's deprecated server behaviors (however they still need to be installed because it uses the database connectivity layer, server behaviors panel, and bindings panel that are otherwise missing from the dreamweaver installation).
DataBridge enhances the standard MySQL server behaviors adding more functionality that didn't exist in Dreamweaver before, but it hasn't been updated for MySQLi yet.
You should always be going to the server behaviors WebAssist->MySQLi folder to apply any MySQLi functionality. Any other UI access points are likely to generate MySQL code.