I'm a big fan of the Torklift Stableloads. They won't ever spring a leak, you never have to keep 5lbs of air in them, they'll never pop.
They will help a little with sway, but that is not their intent. Their intent to to help level out your truck by engaging the overloads sooner. By doing so, it helps with sway a small amount.
But..
Nothing helps with sway more than a sway bar. I prefer Roadmaster, they're much bigger and beefier than Hellwig. I had them on the front and rear of my previous F350 DRW, and it was night and day for sway control.