I'm just relating my experience, which is with a big camper on a 1 ton dually and trying to help others. It doesn't matter to me if any one buys Bilsteins or not. But I think they are a huge waste of money. Not that they are a BAD shock, but they cost almost $100 each, yet they perform they same, or slightly worse than any $25 non-adjustable gas shock from Monroe or Gabriel.
I wasted the $400 on the Bilsteins because I believed it when I read on the misinformation superhighway that they were superior to other shocks, and that they would work awesome on my truck.
Those recommendations were possibly based on the point that someone else made: if you replace a worn out shock with a Bilstein, you may think it is a great shock. Because it is an improvement over worn out OEM shocks. Or else their requirements were less. If you have a fairly light camper with less dampening requirements, the Bilstein will probably work out fine. But the same would happen with a $25 shock.
Dampening requirements vary greatly among different trucks with different campers. And the requirements also change when the camper is off the truck. How can the same shock that is specified for a 1/2 ton truck, that works without being too harsh when the truck is unladen, still be expected to control the suspension of a 1 ton dually with a 3000+ pound camper in the bed, with the center of gravity shifted aft of the rear axle? The same part # shock is specified for both applications, and in my situation, it created a major shortcoming in the shocks performance. They were just too soft to control the load.
That is why I like the Rancho 9000. It can be adjusted to work for my specific application, and it works. And they are about the same price as the non-adjustable Bilsteins.
Also, by taking off my front Monroe Gasmatics and putting on the Bilstein 4600, driving the truck for a year, then putting new Monroe Gas matics back on, I confirmed that the Monroe has noticeably more control than the Bilstein. (for 1/4 the price) .
I'm going to be putting together another camper hauler truck. It will be a 68 Dodge crew cab on a stretched 93 dodge Cummins dually chassis. And I will for sure figure out how to adapt Rancho 9000 shocks onto the front, even tho they are not available for this application. I might have to weld some custom mounts from the frame to the control arms, outside the coil spring.