Does any CTA use IB Automatic Billing? http://individuals.interactivebrokers.com/en/accounts/advisors/advisorWrapFees.php?ib_entity=llc 4 options: 1. Percent of Net Liquidation Value: Entered as an annualized percentage, applied on a daily basis. 2. Flat Fee: Entered as an annualized amount, applied on a daily basis (apportioned by 252 days). 3. Percent of Annual Positive P&L 4. Percentage of Positive Market-to-Market P&L Which option you use? And why? Pros and cons? Would you mind to share your experience? Thanks.