I was always under impression that in order for a Cold air intake to function succesfuly, a fresh saurce of air is brought in. Maybe because most aftermarket air intakes fail is because they rely solely on the oem or factory design to get the air in. And, being that factory box has the size and can keep a larger amount of air volume in the air box for the engine when it needs it, might just be the reason it has been the most sucesful design. I really wonder how the M design compares to the stock. The fact is it is getting the air from the same spot where the oem air box gets it, and plus it holds a smaller volume of air in it. Although it is more resistant to heat, but for how long does it actually do so, as after certain amount of driving time, I'm sure it would heat soak just as factory box. Now, I also wonder if anyone tried fabricating an additional pipe to attach to a factory air box, which would scoop the cold air from under the car while moving. I think this method would be the most effective, as well as heat wrapping the factory box. This would also mean that one would not have a dusty engine bay, however, a filter cleaning might be required more often.
PS--My comments do not reflect bashing in any way, any design, I am just curious to these answers and if anyone has any opinions on this subject.