I don't think there is a product called "Safe-T-Steer", at least google didn't find one. There are similar sounding products, either a Steer-Safe - a centering spring system that forces the steering into an adjusted straight ahead position, or Safe-T-Plus - a hydraulic steering damper system that has a pre-loaded center point that acts mostly as a steering damper. Which one are you asking about?
I'm of the opinion that adding a strong (they tout up to 400 lbs) spring to the steering system forcing into a mechanical center is not the right thing to do. You have caster and trail built into the steering that does that naturally - adjusted properly with good components and it will do as well as that particular axle design can do. The hydraulic damper system is a different thing - it's not designed to maintain center anywhere near as much as it is designed to dampen transient road shock. That is often very beneficial, my truck has one stock and an upgraded one can be a benefit. But the feel will be smoother road feel, not a reduction in wander. At the end of the day, sometimes a truck just handles like a truck - lousy compared to your luxo-car...
Edit - forgot to say that if your Class B has the older style steering box with a drag link and a tie-rod connecting the two front hubs, it's worth while checking that the steering box is centered correctly. It has a built in self-centering action inside it's hydraulic boost mechanism in the power steering, and if you have had alignment or front end work that put the steering box a little off center it will always be applying a small correcting force that can feel a lot like wander.
Brian