I used mine with a Pass X1 and enjoyed it very much, it was like it wasn't even in the room...
I am driving my MCH3-SE C7 with Nuforce's P9 to great effect. Gives more pristine top end, rhythm and pacing than others I have tried. Superb bass and clean and honest midrange w/o smearing. I would not recommend this for an overly bright system but one that's neutral or slightly warmish, this might be the one.