i thought 500k felt on the soft side for outdoor. Just right if it's dusty. I too was perplexed at these super high center diff weights. Didnt make sense to me until i tried it. I dont go any lower than 500k. If on slicks 1mm but prefer a slipper. Will try gear diff at 1.5MM or 2mm if it is available instead of the slipper.
outdoor could be anything, clay/ hard packed dirt..
For me, 500k seemed good for low clay to medium hard packed dirt