The hellwig rear bar is very nice- I recommend it without reservation. Choose one of three setting and you'll find your sweet spot. I put it on a 2013 Laramie and it was a huge improvement over the dinky OEM bar.
The Hellwig is going to cost more, but it's adjustable and probably made of a different spring steel. The factory 22mm works great for me for now and with bushings was less than $100. The part number I believe is 68061789AA.
Basically, the bars are adjustable for stiffness. The outer, or rearmost, setting, from what I understand, is the softest, while the inner, or forward most, setting is the firmest. I'm installing my Hellwig, along with the adjustable end links, tomorrow, so I can check back to confirm, but the above comments are based on what I've read on this and other forums.