needed some snap ring pliers so went to pep boys. Inside of their bin of "clearout" stuff I found a cone filter. Yes I installed it. No I haven't made a heatshield yet. Hasn't thrown a cell yet either.
1st impressions... Louder! first/second/third all have a bit more and it gets the rpm's up quicker... Seat of pants dyno of course. I know... rain/puddles/etc... I made it really easy to swap in my stock airbox. Anyways i need starbucks... Freeway driving :) Yay

are just looks they have no functional behind it. air filter (or cone in this case) is supposed to filter and clear out the air, i would be cautious

I've seen ones that look like window screens.

I did that at one point too. I dont know what year your car is but if you're nDBW your ICM is susceptible to heat. Mine started to overheat without a heatshield and my car would start to misfire or just stall. The ICM isnt that cheap of a part either