I like my open diff: Roush 402. I barely break the tires loose anyway -- 315s! I'm babying anyway right now with the engine being low mileage.
I like sliding around corners too, and you should be able to do it with the BMW open diff. LSDs are great, but this is a road car and you're only going to spin the tires if you really try hard.
My .02, and that's all its worth since I'm a new owner...
Rick, do you miss it? Such a fun ride...
PJ