Every bit helps.
But if you really want to feel the effects of aerodynamics at the track, you'll need to run one of those Race GT-style wings, preferably double-foils.
All street "wings" are for looks only, and some actually increase lift at the back.
I used to not like any add-ons on the Bimmers, but after looking more at the M3 (and especially the CSL) lips and after installing one on my car, I grew to really like it. The profile become aggressive without breaking the lines.
But if you really want to feel the effects of aerodynamics at the track, you'll need to run one of those Race GT-style wings, preferably double-foils. All street "wings" are for looks only, and some actually increase lift at the back.
I used to not like any add-ons on the Bimmers, but after looking more at the M3 (and especially the CSL) lips and after installing one on my car, I grew to really like it. The profile become aggressive without breaking the lines.