You will probably see very minimal gains with either one of those headers. I have the JDM DC w/ 2.5 collector and I am saving up to buy the RMF header. The DC w/ 2.5 inch collector usually runs around 295 for the ceramic. It is the best bang for the buck header but won't make near the power of the RMF, ANR, or Hytec headers. But with any of those you are looking at a good bit more investment money wise. I have been through three different headers on my setup and if I had it to do over again I would definately have waited and gotten the RMF to begin with. It leaves much more to gain as you do more to your car, especially if you are planning on staying NA. If you have future boost plans I say don't do anything but if you want to stay NA do yourself a favor and save a bit more and get the RMF. You'll be glad you did later.