And the Pimco Total Return ETF will put that juice to the test.

FORBES: Pimco Total Return ETF Shines a Light on Transaction Costs

And some of the newer bond ETFs (like PIMCO Total Return ETF, BOND) show signs of being real competitors for bond funds down the road.

FORBES: Five Reasons Bond Funds Are Better Than ETFs

With the initial run of the Pimco Total Return ETF ( BOND), active ETFs and their managers may need to start thinking about the challenges that success could pose to the ETF structure.

FORBES: BOND and the Future of Active ETFs