I installed a Hellwig anti-sway bar on my 3500 dually truck several years ago. I haul heavy 11-1/2 ft Lance slide in truck camper and have been pleased with the results both with the truck loaded with the camper and unloaded. I've had no problems with the Hellwig product hauling my camper thousands of miles. The install was an easy no-drill bolt-on job. See TDR Issue 47 for the installation write up and photos.
Bill