i donno know who did it but it is certainly the worst design right after the OPEN IK's, if you still could find the bottom end cap, put it back there and get bigger bore induction hoses and an ITG panel filter.
Before, I was using pipercross viper once I removed it I realized how bad it was. MPG was pretty bad.
Certainly pipercross viper is not a bad filter but once you put it on any car you should get it remapped. Ok I accept the lean mixture wont damage your car immediately but cannot get 100 % efficiency without remapping your car.
Again maxogen is very nice lookin toy, but still has some problems even though its good design, it still sucks hot air from the engine bay and is pretty expensive. There is a dyno result posted on their website if you carefully check it, they trimmed the lower rpm's data, never showed it. I am 100 % sure that you are losing some power with these induction kits on a standart map using car.
looks nice ollzie this is what i have it looks like a green cotton filter but it has a heatshield round it not sure what though lol (th filter was on the car when bought it)
and yes i know engine bay needs a major clean lol