In a nutshell, a worthwhile mod. The difference was like going from the stock RSB to the 22mm bar. The rear tires are definitely working harder (better) than before as the bar transfers more load to the rear. No oversteer & hardly any understeer, finally a decently balanced car.
The adjustable bar set to hardest setting of the two, it comes with a nice set of re-enforcement plates that install to the stock mounting positions. I put a few turns of Teflon tape on the bar and lubed the bushings w/a bit of anti-seize, we'll see this winter if the bushing squeaks settle in. I am currently running the KW SHS kit, lowered but far from slammed, with fairly aggressive camber settings, -2 up front, -1.75 in rear, 0 toe up front, 1/32 in on rear. Pirelli P-Zero Corsas on SSR Comps w/ 8mm rear spacers & 2mm front spacers, (yeah, I know that rear spacers promote understeer). Haldex mod. Your results may vary.