What you need to look for in shocks is that they are Mono Tube design and that they are charged with some sort of air like Nitrogen. Nitrogen charged shocks have no moisture in them, so they wont get any corrosion inside the shock.
I had a buddy with an IFS truck and Rancho shocks. It road like a brick. I had Doectechs on my current truck back when I had leaves. It road like junk. Some one gave me Pro Comps, same story. Because none of those shocks have any rebound in them. They are just tube with a piston that has holes in it and oil passed through the tube. The oil slows the piston down which slows the suspension but doesn't dampen the ride or help control the suspension, they only slow it down.
I counldn't believe that a charged shock that I counldn't compress with my hands actually made for a softer ride. All Rancho shocks are the same, so are Pro Comps and Doectechs. They all suck. I cant believe I ever had anything but a Bilstien or Fox or something like them. It's a purchase you wont regret.