The factory suspension of my 2015 was well balanced and very entertaining in the canyons with stock tires. Upgraded to coil-overs that have 5k (280#) front and 3k (168#) springs and the balance shifted to mild understeer. The Hotchkis was one of the changes to my suspension setup to correct handling back towards neutral. (I would still be using the Hotchkis if it fits with the Verus diffuser.)
Interesting tidbit: Factory 15' springs were 171# front, 143# rear (54.4% front, 45.6% rear, of total spring weight). This resulted in a neutral-handling FF car with 60/40 forward weight bias. [MENTION=235]koozy[/MENTION] 's post on another thread shows the 17'+ uses softer 154#/131# springs for similar total spring weight ratios (54.0% front, 45.0% rear). The 17'+ also has added front and rear roll stiffness. (@Truth in Ruin mentioned handling differences between his 16' vs 17'.) My 280/168 coil-over springs setup is 62.5% front, 37.5% rear. Without other suspension changes, this resulted in mild understeer.
If you want the rear end to be more "lively", then yes, try the Hotchkis.
There is one negative to the Hotchkis (Eibach, more so). The 10.2 lbs is added unsprung weight. [MENTION=235]koozy[/MENTION], Had to address the weight...
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