S1 is stock. S2 is heh. Go for a CorkSport CST4 or 5 depending on goals. I have one of the first CST4s, like 3rd one for production, and over 70K no problems.
First things first. Holy OG return, @Lex2007 !
Second, AEM made the intakes for Mazda. I personally would use the SRI option for it.
Lastly, what is all that on the filter? Did it just fall apart after so long?
Christine is ready for her 1st winter break. still need to get softer springs swapped in and the spoiler extension. Oh and organize the rest of the garage.