The bad stone phase shifter gives you multiple tones to experiment and never get tired. With two modes, very different, you can play with the settings and get a new sound everytime.
Sold my Phase 90 and got this after seeing in in Reverb's "Potent Pairings: Tame Impala" video. The manual setting pairs nicely with a fuzz pedal. I keep the feedback around 4 O'Clock and love it.
Just added the bad Stone for use with my trusty old Phase 90 Found out days later the Mu-Tron is available as a re-issue ... now to grab one of those as well I guess.
.10-19-19 .. just returned it to GC this morning. Having a Phase 90 and just added a Mercury Flanger tothe Fx line, and Gc's 45 return policy I got to take it back for a refund rather than take a loss / have it sit around collecting dust.