I'd go Non fouler with your custom midpipe, I paid $5 for a pack of 12 at a local auto parts store. No shipping, only takes a few minutes to install, and it pulls the O2 away from the exhaust stream so you won't kill your O2 so quick. The MIL eliminator works also but then you have to worry about the harness, solder, and just be paranoid as I am that's why I went with that instead...