I didn't run two lines clear to the motor. The dual pumps go back into a post filter, and from that post filter there is one line to the motor where it y's in ITP Diesel's fuel bowl delete to the heads.
As for the cost, the second pump cost me $160, the filter heads and filters cost another $70, and with all the fittings and hoses, 5/8" in tank pick-up, and bowl delete, I'm in the complete fuel system about $400.
Compared to a Fass system it is quite a bit less expensive. And the Fass set-up doesn't replace any of the pick-up or feed lines. When you consider the cost of one big aftermarket pump, such as the Aeromotive, this set-up is pretty cost efficient, and seems to work well.