The problem here is heat soaking from inside the engine compartment. While you will draw from the underside of the car, the majority of your air will come from the roof of the engine compartment, where the air is quite warm. That is why the popular CAI set-ups draw from inside the fender. Better to remove that infernal rubber trumpet (the dreded IRT). Though some warm air will be drawn, the proximity of the IRT hole to the IRT fender opening will allow significant draw of cooler air.
I like it. Now all you need is a filter that is open in the front so you can pull the headlight for more cold/ram air when you are racing. The filter in the Johnny Lightning CAI has the open element front, so it shouldn't be to hard to find.
This setup showed a substantial SOTP gain over just removing the silencer. You could feel and hear the sucking from the silencer hole as it was an orifice restriction in the system. Also, I do not see how this has much more heat soak than the PHP or Amazon setup. There was a thread on here where the authors stated that the having the filter in the fender was unnecessary due to the efficiency of the intercooler. I am not sure myself, but my research here also makes me unsure if I want a bend in my intake before my MAF.
I put a digital thermometer with a long lead on the filter and drove around - it never got anywhere as hot in the filter element as it did at the top of the hood liner. And temps became ambient when the car was moving. The AR (and the Paul's ) has a plastic shroud to help keep air above and to the engine side away from the filter, and it does surprisingly well. plus, the filter sits low on the fender cowl in the engine bay. And no 90 deg bends. The debate goes on....
All one needs to do is look at what the quickest and fastest '03 Cobra's are running for intake systems. They wouldn't be going that quick and fast if it didn't work.