I’ve been playing since the 1960’s. I’ve made a living playing guitar. I know first hand how accurate the original strobe tuner was/is... So I can say the Strobostomp HD is every bit as accurate. 1/10 of 1 percent. Compare that to other tuners. Let’s say you have 6 people singing in harmony and each person is within 1- 2 percent +/- f being on pitch vs 1/10 of 1 percent. See the picture. Well worth the few dollars more, especially if you set your own harmonics. Hey, don’t forget about all the extra features. This is a pro pedal.