I bought this tuner to use in tap tuning the mandolins I am building and so I am using only part of it's capabilities and function. That said, it is easy to use and understand and I am quite happy with it. Previously I used Peterson's tuning software, StroboSoft 2.0 but tired of having to bring my computer out to my shop every time I wanted to test something. The 490 starts up in seconds and in combination with the Behringer CS400 compressor and a microphone works flawlessly.
As a musical instrument maker I have several tuning aids which have served me well over the years but I was looking for a device that would recognise more concisely certain notes that other tuners fail to be happy about. Also I wanted a tuner that would measure harmonic positions within a complex sound. This is at times a tall order but I think the Auto Strobe 490 is achieving this. My first tuner was a Yamaha PT4 which cost close to $1000 back in 1976.. it was very good but the Peterson Auto strobe is a great improvement... long may it last. I am a woodwind instrument maker but I also have other types of instruments to tune , Accordion type reeds and some stringed instruments. One feature of this type of tuner is the way it shows the decay of a note. The extreme accuracy may appear to be overkill for musical instrument work but there are times when measuring a pitch to one thousandth of a semitone is usefull.
Use this Peterson Strobe Tuner in my repair shop for Buzz Feiten guitar retrofits. Need that kind of accuracy for the acoustic and classical guitar retrofits. It is incredibly accurate and easy to use. Also looks inpressive in the shop for customers. Nobody ever argues about intonation settings when I fire this up and plug their guitar in. Otherwise its really overkill for other applications, and is pretty expensive. I do not recommend it for anyone other than professional repair shop. For high accuracy at better price, I would recommend the Peterson handheld virtual strobe tuners(if they still are even made), or Stroboflip tuner instead for your home guitar bench setup.