i will be soon running stage 2 (bluefin + Milltek TBE + K&N typhoon CAI) but my eyes are on the K04 upgrade...but i am wondering..will i be changing the exhaust or CAI that i'm investing on right now or i will still be able to use them when i make the upgrade....and one more point, what is the most reliable K04 upgrade in the market now?? as i can see that many ppl have been running this upgrade for a long time now