A picture is worth a thousand words, right?
Automobile 2 - Odds and Ends pictures by kach22i - Photobucket
I say it's a dead even draw at best. I'm 98% sure the custom car is less aero than the stock car.
Most likely those air catchers will capture a pocket of air, while the main air flow goes over it. I don't think they are the main issue.
The main issue is the turbulence caused by the protruding wheel wells. It's nice that the wheels are covered, but that will not make up for the additional turbulence caused by the outcropping of the wheel wells.
Just my opinion, would have to wind tunnel both these cars to be really sure.
I'm positive the creator of this custom car was trying to evoke emotion and initial response over any aerodynamic goals. Maybe as suggested the Audi in I-Robot was an inspiration or influence.
Certainly the Lexus LFA was an inspiration for some of the details.