JSQ
Adventurer
The pictures were only aiming to compare how the MkII was used in Trek compared to MkIII in G4. There sure doesn't seem to be any substantial difference from which one could draw the conclusion the MkIII's were somehow more thoroughly tested than the MkII's.
Mileage.
Trek trucks ran obstacle courses and a little land nav. That's it.
The G4 trucks ran thousands of miles.
Is it really that tough for you?
Can't see the forest for the trees?