Not so sure about Dunlop SP Winter Sport 3D
I just installed a set of Dunlop Winter Sport 3Ds on a set of stock 18" wheels I bought off a forum member. Tire Rack used to suggest these as winter tires for M3s, in 235/40/18 and 255/40/18. That's where I got mine. Apparently, they don't have the 235/40/18 any more, so they're not suggesting these as an M3 tire. But they do have the 245/40/18, which will fit the fronts just fine.
These are replacing the PS2s that came on the rims and were pretty close to the wear bars. Anyway, I should not be making any judgments yet, since I have all of about 50 miles on them, and I've never had a comparable tire. But I'm not particularly blown away so far. OTOH, at least I don't have to worry about the temp being too low any more. Yesterday it was about 35 degrees and raining, and I would NOT have ventured out on the old PS2s in that.
I guess time will tell.