I had the previous generation, the Wintersport M3, on my '05 545i several years back and they worked well here in the 'burbs of NYC in the snow. Are your 3D's brand-new, or did you get them used? If they have three seasons on them, their snow traction may be kaput. If they're brand-new and you just put them on a couple of days ago, they might not have worn off the tire mold release compound yet and so might be a bit slick initially until you get a couple hundred miles on them.
IB E90 M3 ZCP returned to BMW FS