RD415, Hi. Re the stall on tight reversing, mine does that too. It's not the clutch - it's transmission wind-up that locks everything up, due partly to the loads imparted by the limited slip rear differential, and the full time AWD. My Toyota Landcruiser also has the same setup, limited slip diff and full-time AWD and does the same thing. We have a car-park at our local shops that has a speed hump at the rear of each bay, so you have to back out tight, turn and transect the hump all at once. A lot of load-up. I have stalled the MPS6 there on occasion.
Avoiding full lock turns under load is the easiest way to avoid this. If that is not possible, then you can do it in small bites perhaps. It can be overcome by application of more power, but that doesn't reduce the lockup, just enables you to apply sufficient power to overcome the only way the car is going to move and this is by scrubbing the tyres. Cars with fatter tyres will experience it more. You will note that it will not do it, or will do it less under otherwise identical circumstances, on a slippery/gravel surface, as these surfaces enable the tyres to slip easily and relieve the transmission wind-up. You will find that occasionally, the diff will click or groan as the plates slip, depending on the severity of the turn. It sounds painful but doesn't hurt the diff unless you make a habit of it.
In short, no matter how big or how new, or how wonderful your clutch is, it will still do it.
This is an issue often dealt with by 4WD drivers, most particularly where there is no centre diff to compensate. However, talking of making a habit of it, the mining industry used to blow up out lots of FJ45/55/65 gearbox transfer cases (no centre diff) that couldn't handle prolonged low-range 4WD use on tight turns when working underground, even on loose (but still hard and unforgiving) rock surfaces. These cars were often locked permanently in 4WD low range as part of the mine safety directives, so the boxes and transfer cases never got a chance and would last mere months in some cases.