No one else has mentioned it so I guess I have to give my testament to the Hensly Arrow hitch. I tow with a half ton dodge and tow a 24' enclosed with 4'V and 2' extended tong. That is 30' tip to tip. As we all do we tend to take more stuff to the track when we have more room to put it in. I have the 5200# axles so the trailer can carry the weight. I started with a Dual Cam setup and it worked OK. I have a tendency to at least keep the speed limit even if the Hemi is at 5200 RPM in 2nd geer (and it still purrs). Anyway, comming out of VA into NC on 77 always seemed white knuckled as you are going down hill, around curves, and passing tractor trailers. You all know what I am talking about as you put steering input and the trailer wags the truck and you try to slowly add input and keep the wag as small as you can.
With all that being said I started to look for another way. Maybe a dedicated tow vehicle (not the daily driven company truck). I researched some different hitches. Pull rite looked OK. It is basically an upside down fifth wheel. It takes some serious install to make this thing work. Next was the Hensly Arrow. If you do some research on the travel trailer boards you will hear about both of these hitches.
I settled on the Hensly as it worked with my standard receiver hitch. It seemed a little hard to hook up but turned out not that bad. So new they are $3K and were $1.5K on Ebay. I found one on auto trader for $1K and felt I could always Ebay it if it did not work as needed. All I can say now is I would give the $3K for it with what I know now. It took some custom fab to make it work with the trailer but all is very good. I can travel the same roads now and the trailer never transmits it wagging to the truck. It basically uses linkage to triangulate a theortical pivit point at the rear axle and not the rear bumper.
Anyway, enough but it really works and is worth the effort to find that Ebay find.
Michael
Ok have always used the Frition type sway control when towing, But ended up with a Dual cam control system when ordering a replacement. 
. any pros or cons against the Dual cam Type? My equalizer bars have the required end for the Dual cam control. 24 Ft trailer woth the usual load of spares,tires,tools, and 2nd gen RX-7. Thanks for any input 