looks better without. the rear deck lid has integrated spoiler as is, so adding an additional spoiler looks like too many breaks in the design. I doubt it serves any functional purpose. That thing is not generating any downforce or improving drag at all.
fail.
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2014 335i RWD: ZMM, ZDA, ZDH, ZPP, ZTP, 2NH, 2TB, 5DL; Z4A MPPK; AW ext / VB int
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