Get the gauges...they help you keep an eye on things, and you can see when something is not right. For example, one time about a month after my install, I noticed the air/fuel was running near full lean while driving. Not good! Had I floored it, could have gone BOOM. But I saw it was way too lean and stopped and corrected the problem (forgot what it was).

Yes, you can do without them. But is it worth saving a few hundred bucks? I dont think so