I have a Wyetech Opal and it surely should be mentioned as a contender. The reason you never see them on the used market is that it is a "legacy" product; built to last a lifetime and with so pristine and reliable a design, and with such high construction and parts quality, owners like myself have no interest whatsoever in the preamp "flavor of the month". And at the price it is a great value. It is the one component in my system I have NEVER thought of replacing.
System:
Wyetech Opal
Krell 300cx amp
Dodson 218 DAC
CEC TL-1X transprt with RAM mods (includ. Superclock 3)
Von Schweikert VR5 HSE spkrs
Elrod Statement,2 Sig and Nordost Valhalla PC's
Valhalla and AQ Sky IC's
Stealth Sextet bal. digicable
PAD Venustas spkr cables.
Original Hydra power cond.
System:
Wyetech Opal
Krell 300cx amp
Dodson 218 DAC
CEC TL-1X transprt with RAM mods (includ. Superclock 3)
Von Schweikert VR5 HSE spkrs
Elrod Statement,2 Sig and Nordost Valhalla PC's
Valhalla and AQ Sky IC's
Stealth Sextet bal. digicable
PAD Venustas spkr cables.
Original Hydra power cond.