Filter upgrades rarely result in MPG gains. If anything expect a little more power. The "partition" they are talking about is to isolate the filter from the hot air from the motor, so only cold air from the fender gets sucked in.
1) I have seen many filters increase mpg. You have more power using same amount of fuel, therefore can go further. Mine is not for some reason.
2) I didnt ask what the significance of "partitions" are. I clearly stated WHAT they are used for and asked if my setup required one
1) I could argue that day in and day out. So I wont.
2) I explained it. It keeps the hot air away from the filter so more cold air gets drawn in. Cold air is denser. Since the amount of fuel that can be burned is directly linked to the amount of air available, denser air equals more fuel that can be burned, creating more power.