I rarely stumble upon a product that is truly flawless. But the Boss TU-3 is indeed flawless. From the design, ease of use, and materials used, to its overall sturdiness and precision, this is the ultimate tuner. No other tuner I’ve ever used has come close to this one. It has the fastest response, is the most precise, and is the most straightforward of them all. If you really, and I mean REALLY, want to find a con, this is it: you have to plug it in. That’s the only con I can think of, but it’s certainly not a bad thing for me, as I’m not lazy and I like cables – they always feel like the metering is more precise than anything you could mount on your guitar’s headstock.
To sum it up: highly, highly recommended. Change any other tuner you might have to this one, and you’ll want to use it forever and a day.