Its good. Not awesome.

Its a good general tuner in the needle mode and is accurate using it. The stream mode isnt as accurate as something like the Sonic Research ST series strobe tuner. The strobe seems to lock in at a range of pitches and wont move until you really go out of tune. The PolyTune function triggers low on almost all strings even after you tune using the needle mode. Lastly, for some reason it will not track the low E string. Its probably worth the $5. Im glad I didnt spend the $99 on the real stomp box version.

Mark B from NC about PolyTune, v1.1.0