I don't want to get in a big argument about it, but I would tend to find the wings being very effective to be dubious at best.
To be blunt, our understanding of aerodynamics has increased greatly since the Saleen wing debuted in 1983. The "divisive" 2000 Cobra R wing was often blasted by people as being too high and ugly, but the reasoning from Ford was sound - if it was too low, it did nothing. This is also why all the race cars, such as the Maximum Motorsports one...
use a big ass wing that sits above the roof - because that is where they are most effective.
Still, I guess it can't be ruled out that a Saleen wing does nothing since I don't have access to a wind tunnel, but as with most pieces for street cars I would lean towards 99% aesthetics.