I purchased the set of these bars from Bimmerworld but currently only running the front sway, set at position 2. I'm going to install the rear when I do my subframe bushings etc like what most people are doing.
I've done 3 trackdays with the front bar installed and so far I love it! My turn in definitely improved and the car overall feels more planted and is predictable. No understeer or negative effects that I can report at the moment.
I paired my front bar with the BimmerWorld 12-13.5” swaybar end links...highly recommend those as well. Quality pieces!
IMG_4121 by
dj_dub, on Flickr
IMG_4127 by
dj_dub, on Flickr
4TR_4831 by
dj_dub, on Flickr