The Hellwig sway bar kits are solid steel instead of the hollow tube design like the Eibach. I have ordered the new front and rear Hellwig kits at ebay, to be installed soon. They are kit #'s 7701 and 7702. $7701 is $365.51 and 7702 is $262.59 and I bought from seller "neverenoughauto".
Not saying the Eibach kits are not quality at all but I would prefer the solid steel bars instead of the hollow bars. I just installed new KYB shocks but I agree with
@91RS, at least match the 5100's or install known age all new shocks. The shocks control front and rear spring bounce oscillations and to a point the sway from centerline but the sway bar kits really will stiffen up that sway. I am really looking forward to the different comparison when I get those Hellwig kits on.