Price paid: $ 250
Purchased from: http://www.hermidaaudio.com/
Sound — 10
I use it with a Strat w/ either Lace Hot Golds or Vintage Noiseless pups in it, a LP with stock Burstbuckers and an SG with stock 57 Classics. I use it with a Tube Driver boosting it for higher gain and into a delay of some sort into a Fender DeVille 4X10. IMO, it sounds very much like Eric Johnson, Robben Ford, John Scofield, Chris Polan in Ohm, Allan Holdsworth, etc., all depending on how you set it. It cleans up very well with picking dynamics and volume control manipulation. My only complaint is that it gets very bad radio interference at my practice space. It's dead silent everywhere else though.
Overall Impression — 9
I play Blues, Jazz, Fusion and Classic Rock with it. It works wonderfully for all of those. I've been playing ~6 years as of this review. I own a Hermida Mosferatu, Butler Tube Driver, Vintage TS808, etc. and none sound as good to my ears as the ZD. If it were stolen, I would definitely get another one; as of right now it's the core part of my dirty tone.
Reliability & Durability — 10
Yes, it is extremely reliable. If it does manage to break, Alf will be glad to help you. I have gigged with it, although I brought my Mosferatu along just in case. I've never had any problems with it. The only thing is my Mosferatu had a bad footswitch. I got it repaired promptly though.
Ease of Use — 9
The pedal is extremely simple to use. It's got four knobs, Gain, Voice, Tone and Volume. Gain, Volume and Tone are obvious. The Voice knob works somewhat like a presence knob. I keep it pretty high. My settings are typically as follows: Gain-12:00, Voice-3:00, Tone-10:30, volume at a slight boost to dry signal.