The question is "What do you expect to achieve with the Ride Rites?". As Jim Shryker notes, they are excellent for leveling a load and help control sway. They do not increase the capacity of your rear springs or the GVWR of the vehicle, but they may help it handle better when heavily loaded.
Do you have a handling problem? If so, what is it? What do you carry/haul with the truck? With some background, we might be able to help determine if the Ride Rites will be beneficial to you. They are a good product, but not a panacea.