i have one and it is a good pedal. with a les paul you can go from a good classic crunch and grind to a biting growling attack. its just a matter of mixing your amp/guitar settings to the pedal. its not too good on the blues but i might not have the right mix yet.

i dont know if this happens on all of them but if i try to use it with my fender strat(60's special reverse s/s/s) i get a horrible whine and feedback like you wouldnt believe. i have traced the problem either to the pick ups (stock but they dont do it with my other pedals.) or the pedal its self.