Expenses Approval - Query instead of Application Class

As Oracle delivered, the approval process for Expenses uses application class on the user list setup to define and find who to send the expense transactions to for approval (e.g. Expense Report Approver user list uses the Root Package 'EX' and App Class Path of Approval List:ERApproverList).

What features will be lost by using a query to determine who to send these transactions to? Will the ability to user privilege templates/risk template be lost?