Typically in the past intakes offered a nice cheap way to increase horsepower on these cars. With the MK7 this has changed and the stock intake itself is very nice and works very well. It works so good you really dont need to replace the stock intake unless you go to a bigger turbo, this is typically STG3 for most tuners. Intakes are not as cheap anymore as the used to so this upgrade value has diminished over time.
Part of the intake actually acts as a Helmholtz resonator. Specifically what their end goal was is unknown but it could of been for changing the resonating frequency of the intake to increase flow or just to reduce/enhance sound at a specific frequency.
The only real reason to replace the stock intake is if you want to hear the sound of your turbo more. A third party intake will allow the sound of the turbo to be more prominent. Just be careful though that you dont get an intake that gets air from within the engine bay. These engines get heat soaked very quickly and grabbing HOT air from the engine bay can actually cause performance degrade no matter how well it flows.
There are two small things you can do to increase flow with the current intake. The first is a performance air filter and the other is to remove the tray thats located below the filter in the intake housing. Some refer to this tray as the snowguard.
So in short I would not upgrade your intake until you go for a bigger turbo. And if you do decide to upgrade your intake, make sure it pulls cold air from outside your engine bay. Some of these intakes use the bottom half of the stock airbox.