I have an Imagine Injection intake on my Nomad... and I'm running a "modified" screen... I took the "foam" out from inbetween the mesh - and put fine stainless steel window screen in it's place.
I drive my car daily in the summer... and have driven it on many long trips. Not sure of the milage - cause I just don't pay any attention to that... but I know of a guy in AridZona that has 30K miles on this kind of "filtration" (that is not what this is - there's nothing filtered at all of course!)
Just don't drive down a dusty dirt road is all!!