Smoother, much smoother. The 5100s with stock springs were better than stock, but seemed to jar a bit over larger bumps and werent anything special on the highway.
These are on a whole differnet level in terms of the ride smoothness on road. Because they use a larger shock with more dampening force, they are able to use a lighter, linear rate spring which provides an awesome ride that isnt stiff, but not loose either. There is less front end dip under braking, the truck stays much flatter during freeway on-ramps and corners and the freeway ride is caddy smooth. Less body roll too!