Welcome to the forum, you'll find the members on here are a friendly and helpful bunch :)
I'm assuming you are looking at getting the panel filter rather than the cone filter? If you are trying to increase power then I would advise an engine remap instead as I'll improve bhp and potentially mpg. You'll only gain 5,bhp tops with an uprated panel filter.and slightly improved acceleration (in theory).
Obviously if your Q7 is still within warranty than the filter may void this as it's not a genuine Audi component.
Obviously the benefit would be that it never has to be replaced and you will get a lifetime warranty.
Cheers
Steve