NetSuite Invoice Best Practices

Please tell me we are not the only NetSuite customers who are struggling with NetSuite's invoicing features...

Our request:
Invoice per month based on the total number of user licenses (we are around 37 or so).  It is understood if we add/remove licenses, we will receive a fractional invoice but we haven't done this in 3+ months.  We continue to receive 4+ invoices each month and it is impossible to allocate costs appropriately throughout our company. 

Please let me know that we are not alone...I have talked to our Sales Rep and his boss and no actions are being taken other than "we understand, other customers over the past 6-8 months have made the same request."  How many more customers need to speak up before something is done?