Thats the MK3 version,
As a stand alone item i dont think you will notice any difference on the car (maybe a little bit more noise) but certainly on the MK3 this is one of the mods you do to get the smoothest, uninterupted flow of air into and out of the turbo thus giving max power from your stage 1/2/3 map.
As you have already mapped the car I would talk to guys who did the map and ask them if this will work well with your car setup.