Sounds like "Toddco & the Boys" are going overboard and making something for anything ! Has anybody checked the half shaft drive-line angles with them yet ?
I believe they originally were invented for 'utes' to level the ride height for wanabe cowboys who never actually used their rigs for haul'in and wanted the stance of their trucks to look the same front to rear. Most utilities of the era were designed with carrying capacity in mind, so rear ends always seemed to sit higher dudes.
As such they are still only sold for front end lifts on most pickups, whereas us Range Rover folk had more of an inclination towards coil spring isolators or air bags.