I just finished installing my height sensors, and frankly it was way easier than I ever anticipated. It took me a couple hours working slowly, triple-checking everything, but it was one of the least difficult aspects of installing everything.
The accuracy is amazing as well, the whole 1/8" talk is no joke. I can measure my fender-to-ground, and it's always dead on.
After driving with it all installed, I decided that e-level was worth every penny