No scangauge here--yet. It may be something I consider in the future, but so far, I actually like the simplicity of the eco light (although it's often washed out by sunlight). I know most "hypermilers" scoff at the eco light and claim that it's a poor effort from GM in light of most hybrid cars' complex systems, but for us, it's just right. I'm pretty sure that my wife would pay little attention to it, and I'd be just the opposite--staring intently at the display and paying a lot less attention to the road. Maybe someday, though. It's a neat device. I do like the idea of checking and clearing codes.