Puritan PSM156

I have been using a puritan 156 with their upgraded power cord for about 6 months and am impressed by the improvement in sound, especially the clarity of the bass, the articulation and separation in the midrange and lack of harshness in the treble and timbre.  After experimentation, I have both my preamp and mono block amps in the 156 along with the DAC and my SoundSmith Strain Gauge.  In fact, with the 156 I could clearly hear the difference between the Rogue Audio Stereo100 and Apollo Dark amps, a DAVE vs a Rossini vs a Briscati DAC etc. (I guess you could quip that being able to hear the difference was a "downside" since I ended up trading by Stereo 100 for the Apollos and my DAVE for the Rossini. ) There is a "break-in" period.  My system also consists of Nordost Valhalla cables and Sonus faber Amati tradition speakers so is fairly revealing.  Whether the 156 is beneficial also depends on the quality of your electrical service.  I do have a dedicated 20A circuit and prior to the power company replacing a transformer near my house, I did not seem to have significant noise.  But, about 8 months ago, when the transformer was replaced, I could clearly hear a difference despite the dedicated circuit.  The 156 "fixed" the problem.