The 5100's are lot better than anything else in new shocks, a huge improvement form worn shocks. Ride quality is really not effect as shocks don't really change that, but, handling and performance under hard use are light years better. I don't like a caddy ride in an HD truck so the more aggressive valving just make it fell much more solid, the rebound damping is MUCH better than any OE shock. With a suspension system they really make speed bumps feel like cow chips.
Now, if you want more shock under harder use the 5160's a great shock for a heavy truck and rough roads. They are a step over the 5100's and not as noisy or stiff as Kings or Fox.