well intakes have been discussed a lot. closed vs open and yada yada. in the end, i don't think it matters as much as you think. the main thing about the gruppe M (authentic) is that its filter is conical and has a large surface area which is also less restrictive than stock. moreover, it has a large volume of air to work with unlike a closed intake. the front duct also has scoops too. when you're car is moving, i don't think the hot air will be a big difference because the sides closest to the engine are shielded.
as far as the rep goes, i'm sure it's about the same. the front duct, if it comes with one probably wont have scoops. the filter will probably be a K&N (used by authentic). only difference might be quality of the cf and fitment.. but functionally it should be about the same.
just FYI i've owned gruppe M (authentic) in the past, but now i have the oem performance intake. main reasons for switching was because at the time, i lived in a really dusty area--like quite literally a day after parking, my car would have a layer of dust on it. so, open intake probably not the best idea if i don't want to deal with cleaning the filter all the time
looking for a PreLCI Black Sapphire e90 front bumper without license plate holes
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