I have the mountune air box, FMIC, and boost pipe set.
I was the first to purchase the mountune FMIC here in the US and glad to put it in.
What has been said above is correct, it does not add HP but it does keep the air charge temp more constant and it dissipates heat soak more quickly.
The closed air box keeps hot engine compartment air from getting in.
It also draws additional cool air via the hose in the bottom the box.
I Just attached mine to the plastic charge pipe so that cool air is drawn from the center and beneath the car for better air flow.
The use of the pores hose is used so that water can not be sucked up do to its lower intake level (although this is still impossible).
I choose not to place this hose behind the fog light as this provides poor air flow and the fog light itself is a heat source (I keep mine on all the time).
The boost hoses don't do much however the metal boost pipe does provide better flow as it removes the "muffler" that causes turbulence.
As for the rest of the hoses, as I said, don't do much except add color/looks, except the silicone hose will also last much longer than the OE rubber.
Now for the Mishimoto oil catch can that westcoaST is using.
I looks to be exactly the same as I what am using in size, shape, and setup.
It can be mounted in the back of the engine bay and when connected with OE hoses, it looks almost Original Equipment.
All I can say here is Good Choice.
Dave