Well I finally got myself one of these - I have long wanted a good quality tuner that is true bypass. I've actually taken the back off to try and see if it really is TBP but it's difficult to tell. Certainly my brief tests of playing through it bypassed and then without it in the signal path at all seem to indicate that if not TBP then it doesn't mess with my tone. I will experiment some more on this. But it works really well as a tuner. there is very little twitchiness to it and my 335 is perfectly in tune as a result. It's difficult to describe, but the way the LEDs operate makes it very easy to use. They fade in and out rather than blink on and off. And the whole unit is smaller than I thought it would be. It's pretty cool. I may be on the way to having one less pedal (A/B box) on my board! Less is more!