How well does a Cowl Induction system work?

[MrQuick]

Well its cheap, no cowl hood needed, and its the best air you can get. That area has very high pressure and its all clean air.
The bad...combustion/fuel smell with ac or vents on.
Loss of vent pressure in car.
Cuting a hole in your fire wall might be a down side for some.
Nascar still uses this style set up, Im not sure why GM didn't use it more.I guess they liked the look of the hood??