I purchased a used Promitheus solid-state DAC from Todd (skullguise).
It was an elaborate transaction, through no fault of Todd's. In fact, he acted in a way that was exemplary of what any of us would wish to encounter from another member selling gear on Headfi.
The Promitheus DAC is a well-received, moderately expensive component. When Todd advertised the item, he was aware that it had minor problems with electronic hum--problems that he had already invested a huge amount of time and effort in trying to resolve with the manufacturer. When he advertised the DAC in the Sales Forums, he went to great lengths to explain in detail precisely what the problem was and also his frustrating encounters with the manufacturer, who had offered limited support. Having advertised these problems, Todd substantially discounted the item.
When I contacted him, I asked him to explain the problems all over again, only in more detail. Todd not only replied to all of my questions thoughtfully and candidly, but at last he offered me an unconditional refund guarantee.
I've been very fortunate to deal with friendly, knowledgeable sellers in the Headfi community, but, without a doubt, Todd has been the most honest and committed vendor I have yet dealt with. I am convinced that he has sacrificed his time and profit to ensure *my* satisfaction. You can't imagine a better person to deal with or a more pleasant sales experience.
Many thanks, Todd.