I posted a lot of data on this a few years ago. I'm on my 3rd season with a DW pump on E85. I run high boost pressure and subsequently high fuel pressure, up to 75psi. The DW pump has been able to support that up to approximately 75% duty on my 80lb injectors. After that the fuel pressure falls off a little.
Just recently (in it's 3rd season) I added a Caspers volt booster to give the pump a little extra push, since it's no spring chicken anymore.
My setup is the following:
stock fuel lines, fuel filter and fuel rail
80lb injectors
Casper's hot wire kit
Racetronix fuel pump bulkhead wiring kit (to replace the wiring that goes into the tank)
stock fuel hanger, tweaked and trimmed to hold the DW300
replaceing the bulkhead wiring was critical to the pumps performance. the factory stuff was worn out and weak to begin with. the fuel pressure capability improved substantially with the new wiring.