I went with the Reese HP WD system with the square trunnion bars. I also upgraded to the "forged" shank (part that slides into your vehicles receiver hitch) rather than the cheaper "cast" shank. 4 years ago it was about $450 delivered for everything including shank and ball. It was this one here. Reese HP trunnion bars WD 800 lbs
. The shank will cost ya about $125 for the cast and $170 for a forged one more.
The spring bars that are round, are the cheaper style, the square ones are called trunnion bars.
You can get the basic WD set-up (round bars and a cast shank for $350
One reason I went with a forged shank, a buddy showed me his "cast" shank that broke right in half pulling out of a gas station dip. Ya, 2" thick cast material just snapped in half.
Before I had my truck I pulled another RV trailer a foot shorter with my 4Runner SUV (V-8) with just the friction sway control....It helped a little with sway, but not much with the bouncy bouncy and leveling out the load going down the road. You feel so much more in control with a WD system. When I got the new 26' Aerolite a WD was the only way to go. Even pulling this Rv with the 4Runner, I noticed right away how level the ride was. Here picture
The only reason I bought a new truck was that the 4Runner was 9 years old and we were going to AK. this summer.