Navison is alive and well but is not currently distributed in the U.S. Warranty and service work is available at http://www.navisonaudio.com/en. This unit should be purchased with the OTL amps for a harmonious combo. Many hours of enjoyable listening in my office in Ann Arbor. See review of Mk1 at http://www.6moons.com/audioreviews/navison/prepower.html.
Great deal for audiophile tube sound. A wonderful way to get in on OTL sound (hard to find) at bargain basement price. No tubes are included with this unit.