Never played the Hartke, but I own the MXR and i'm very fond of it. Very good tones, no hum, build like a tank, reliable and precise eq !
What could you expect more from it that the Hartke has and the MXR hasn't ?
IF the hartke is as good as the mxr, only the tone-shaping can make the difference, but only for YOU. So ... try and choose !
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