If this was a Land Rover forum, you would have passionate discussion on the optimum number of splines on your half shafts. Here much of the discussion seems to be US-centric, possibly due to the frequency of tearing apart and rebuilding vehicles with stronger axles/diffs to meet the specific application/hobby, mainly rockcrawling (?).
I am going to "assume" that Carrero and Magna have a depth of knowledge based on the types of vehicles they have been involved with, to spec the axles and diff to meet the needs of the vehicle in its intended application and not even consider what could/should be swapped out..... And If it is proved wrong, either Carrero or the aftermarket will do something to eliminate the weakness.
Early in ownership of my D90, I pulled the 3rd members front and rear and replaced them with locking diffs from Jack McNamara in Australia: way better than ARB's, used low pinion R&P from Toyota and a much better actual locking mechanism (if you have ever fitted ARB;s. that fiddly little copper tubing from the locking mechanism to the housing, for me, was a weak point!). These were available with both vacuum or positive pressure actuation: I got positive pressure, as I alreadt had fitted an engine-driven compressor, and ran lines from my air tank through pneumatic switches, so the entire system is pneumatid, without those fussy relays...)
And the lockers quickly demonstrated the weakness of the half-shafts, but in the Defender, this is an easy swap, with hardened shafts available from many suppliers (I got mine fron Bill Davis at Great Basin Rovers (oops! GBR, since Land Rover North America got nasty and prohibited the use of the name "Rover",,,,,).
So, I am familiar wit the concept of swapping components to strengthen the vehicle. But am happy to wait and see how the Carrero axles handle the "work" before going into a big "guessing game" of how to upgrade (if necessary.....)
