I don't see why anyone would spend more on this amp ,when the Questyle CMA800r headphone amp appears to be much more desirable . So unless someone is using the HFM He 6 Hps (or as I currently like to call them "the ridiculously inefficient , slightly midrange deficient, made in someone's garage ergonomics skullcrusher headphones") this amp is a very hard sell in my opinion !