I myself don't need a Rev limiter. Just my Tachometer w/ shift light and my b&m shifter. I have never blown an engine on any of my many cars I've built. You can also get used to the sound of the engine as well. Most times I don't even have to look. But for safety purposes and cost then i'd go with the e-curve. The add on ones are for when you already have a set up and need to add it to what you already have.
