Well, it's got a barrier between the engine bay and the filter. My assumption is that it fits up against the inner liner on the hood to seal the top up. I however don't see any reliefs in it for the air intake from the front, so not sure where it's drawing air from.
The factory air box should be tolerable as a "cold air" intake. It's sealed from the engine bay and pulls air from the front inner lip of the grill. You can always get the snorkel add on to force more cold air in.
Good observation and not an assumption by any means. Yes, the IFX Intake has been around a little while.
To the a point. Look at the heat shield, it blocks the actual air inlet for the VN. The inlet to the airbox is crucial for incoming air and to keep IAT's lower and at ambient temps. Its blocking the dynamic flow. You can modify the front part of the heat shield by cutting slots, removing the front flap or drilling a 3" hole but without this, it's not a viable alternative. It's made for the i30N primarily. Australia doesn't sell the VN yet, so IFX aren't aware of the inflow requirements for the stock VN airbox.
Remember, air takes the most direct unobstructed route. It won't move around the heat shield in a S pattern, which has been made by means of the heat shield. Cut away the front flap or drill it and the air will pass directly thru the area. There is no air flow from underneath on the VN, like the i30N near the wheel well. So, it's actually attempting to force the air around the heat shield. Not going to work for our application, unless modified.
I'll contact IFX and let them know, they're going to have to produce something more viable for the VN to sell the here.