Cobra Engineering LLC

Ford has sold the factory "oil cooler" as a cooler for marketing purposes. It is in fact a oil heater. But not all the time. It is designed to get the oil up to temp (ideally above 180*) as fast as possible. Remember that the coolant at startup does not go through the radiator. Instead it is diverted back to the block until the thermostat opens up. This not only gets the temp up quicker, it also heats the oil quicker. This is all about emissions. Also oil works best when it's a consistent temp.
There are many reasons for eliminating this piece. You can run a much larger oil filter when you remotely mount it. Many want to move the thermostat to the upper hose thus eliminating much of the hose maze off the lower radiator hose.
Keep in mind it is always a good idea to let your engine get to temp before driving.
Many problems arise when the oil isn't at temp before circulating.
If you run a after market true oil cooler you NEED to have a oil thermostat in line so you don't over cool the oil.

As you come to expect from Cobra Engineering this piece is superior to all other "plates" on the market. These are profiled on both sides to help the coolant smoothly move to the block.