Although not technically a factory car in the truest sense, the Blitzen does have a front LSD, and a damn good one at that. Having all three diffs limited-slip is a real work of art. It means your drivetrain is working its hardest to keep up with the traction. Some people say having all LSDs will cause more parts to fall off your car. I guess I'm not sure how strong an LSD is to an open diff.
Anyway, I've driven an RB5 with full LSD support on a snowy road with Hakkas on and I think the LSDs had the biggest role in keeping me out of the ditch. You could almost feel the torque tranferring to the outside tyres on a corner. In a way it almost makes the car whatever-wheel-drive it needs to be at the time. On acceration it moves it rear and on decel (especially with LFB) it moves power to the front. I think the Skyline did a better job of torque tranferrence but that was electronically-controlled and could always fail. Keep in mind all of this testing was on icy/snowy roads so slip was a little more pronounced than on pavement. I was lucky enough to be able to really realize how much fun these things can be.