I know that if you are concerned with clean air going into your engine, then the AIS it is the best filter. I think that an important improvement with the AIS is to do the zoodad mod on the header panel in front of the intake tube.
Here's an interesting thing I discovered...After installing the AIS, I would always see the filterminder tripped. I then did the zoodad mod and it still tripped all the time. Then one day I had the grill off the truck and noticed that the rubber matting that lies in front of the header panel, was overhanging the hole I cut for the zoodad mod by about an 1/8 inch. For giggles, I trimmed the matting back to about a 1/4" larger than the header panel hole I cut. From that point on, I have never tripped the filterminder. So, I have concluded (at least on my truck) that the zoodad definitely increases cold air flow to the filter and that any impediment (I think, but don't know, it has to do with turbulence) of the air makes a bug difference within the filter box. If I didn't live in the dustbowl of Nevada, I'd probably get the foam sleeve to the wheel well for the AIS...but that would be brutal on the filter in this environment.