I have a digital tuner built in to my Orange Crush amp, the Fender tuning app on my smartphone, and now the ST-2. I ran all three simultaneously, and all three are in agreement as to what constitutes "in tune". The Orange digital tuner is the least accurate only because it seems to have a slightly wider range of what qualifies as in tune. The Fender app exceeds expectations. I suppose maybe this will vary from smartphone to smartphone due to the microphone. But, it is extremely easy to use and allows for exact adjustments. Visually, I think I prefer the Fender app over the Snark. But, the edge would go to the Snark due to the vibration setting. The snark will not be affected by background noise, or even someone else playing in the same room. You can also tune without amplification, which is a plus. The construction is nice. It has two pivot points that move freely and stay put. The price was great too. I see no reason to pay any more. This review is for the ST-2 only.