i did all those mods at 1st header, aem cold air, pulleys,exhaust, mam midpipe with no cats, in the end i couldnt take having no power so i went turbo. was happeir after that. what did it in for me with na, i was driving down the road one day and a toyota 4 runner was running next to me i wanted to get over in the next lane , i guess he didnt want me to so he accelerated and my protege couldnt keep up. Now with a turbo i had the same senerio, a supercharged nissan frontier was going next to me and i needed to get over, well i guess va beach has some assholes so he got offended when i tried to pass well he didnt know i was turboed and i blew him out of the water. with the money turbo is the way to go, with all these used kits springing up i wouls get that instead. I sold my kit on here 3 years ago for 1500 for everthing, msp ecu, kit intercooler, exhuast, programmer.(cryhard)