Peterson Strobostomp
Turbo Tuner ST-200
Korg Pitchblack
I'm thinking about picking up the Turbo Tuner. Peterson was the standard top tier one for a while, but from what I'm reading, the Turbo Tuner is superior to it. The Pitchblack is also great, but more for an easy to read display. Still accurate, but the other 2 beat it.
Check out this video comparing the Strobostomp and the turbo tuner. The pitch detection on the TT is extremely fast.
http://www.youtube.com/watch?v=8bY9H7ec6_0
