Nog een uit de lage landen hier ;-) In my experience the key feature of industrial bearings is not so much that they last forever (although King's allegedly do) but that they are easy to replace.
So what do you mean by "last forever"?
As an Engineer I am fascinated by the idea of making things last "forever" and apologies up front for rambling on for a bit in your thread. There are many ways to make things last, best illustrated by a few fundamentally different approaches: first the "Toyota" way: hone your engineering and manufacturing to perfection by 30 years of continuous improvement and produce the Lancruiser/Hilux, they will not break down (The King hub option).
Second the Land Rover way: reduce the design to it's essence, simple, robust and minimalist, and fit it with cheap and common components that you make widely available. Then assemble it such that everything can be (re)built with two spanners, a hammer and a pair of pliers. It will break down, but everything can be fixed (The XT 735 with cup and cone bearings fit this I guess and Tom Ritchey is good at this too)
I owned a Landcruiser for 6 years, and I rode it in town, on the motorway, in the mountains, across gravel planes, through rock gardens, in sand dunes, over the sabqa and on the beach, unbelievable machines. So are King headsets, but I've only owned a king since a year or so and never can see myself justify the premium price of their hubs. And thinking about it, a Landcruiser actually is not even more expensive ...
I've ridden various LaRo's too (I'm talking Defenders here) and the experience is not to be compared. But I don't think lightly of the Land Rover achievements: minimalist is an art, not trivial at all and Land Rovers in the 3rd world do last forever, Kudos. My Ritchey Logic headset in the Heckler is stil going strong, for all of 7 quid back in '97.
I've seen Arab fishermen park 40! year old ex-forces Mk1 pick-ups on the beach to go fishing. On their return with a full boat they drive the LaRo into the sea to pull the boat ashore, load the catch in the icebox on the flatbed, fit the crew next to it and drive off to the fish market. They have done so for 20 odd years, and probably still do as I type this ..... Amazing cars.
If you are still reading this, thanks and Enjoy!!