alright..im running nitrous and right now via a venom system..here are some thoughts.. ZEX..first off, is not a cheap ass N20 system, that is just ignorance telling you otherwise. Currently there are no N20 systems designed specificly for P5/MSP/MP3's.. The system im running right now is the Venom VCN-1000 w/ the 400 controller. Now, that system is still in R&D, im guinea pigging it. The system was designed for a Focus since they share basically the same motor. Now, as for what you'll need to run N20..its quite simple..depending on how you approach it, computer/throttle controlled (ZEX, VENOM) or button style powershot (NOS, Edelbrock, Nitrousworks) I would definetly recommend using a computer controlled system..just due to the ease of install and how it "adapts" to your motor's capabilities. With powershot you would need to have a deeper understanding of your motors capabilites and you'd be looking into ignition systems, etc..Right now, the only way you'll be able to set up a realiable and "safe" N20 system would be by retrofitting the focus ZX3 kit. Im sure VENOM would walk you through it. As for the ECU, that wouldn't make much difference for you. If and when you get this system, make sure you pick up Venom's 400 controller, it helps your motor push out extra power and allows it to work smoother with the N20..Let me know if you have any other questions. -Kyle