How much is the aerodynamics improved from seals like these?
Honestly... Slightly...
Very slightly.
It does clean up the turbulence in the air that slips off the sides of the hood (Difficult to explain)
At very high speeds it will reduce buffeting of the hood it's self (also difficult to explain)
Basically I would consider it cosmetic for a street driven car.
We have other stuff we will be reproducing in the works... Not available just yet.