All user reviews for the Peterson 490ST Autostrobe

I use it as accordion tuner for fifteen years.
It is extremely accurate, the reading is easy.
It allows for an excellent and accurate work quickly enough.
But he did a lot of noise, and the time of change from one note to another is too long, sometimes several seconds. It has been improved with the change of ROM and stepper motor a year ago (free service, except the engine)
Possibility of other tunings temperate is useful on diatonic instruments.
+: Precision, reliability
-: Operating noise, slow change of note.