I think comparing cars is irrelevant, just look at evos, I had my wing removed for a few days just to try it out and it does make a huge difference. Evo with wing > Evo without wing. I was on wide on ramps and it felt closer to the limit in the turns without the wing then with it for sure. I wasn't even testing or thinking about it but you just know.

 

The CHMSL on the CTS-V is an integrated spoiler.