The main benefit of charcoal air filters that I know about are their odor eliminating properties. I would bet you are going to smell even more outside pollutants with the plain filter. I would have gone with the charcoal one personally.

You e70 guys have it rough though. Your micronfilters are about twice as much as us e53 guys from what I see. I can get an OEM Mann charcoal filter for under $30.

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Profeshenal spellar