I own Cyber 800 for about a year and I'm very happy with them . I got them from a N.J show room of "Quest for Sound" . I talk to Steve (owner of the store & dealer for Opera Audio line) before the show about these amp. but simply could not commit financially. At the end of the show he gave me an offer I couldn't resist. After getting home I set them up with my Martin Logans Aerius I & listen. I was very impressed what I was hearing. The vocal were cleaner more redefine , stage was deeper with more layers then before. Bass was punchier & over all more musical in the same time. Sound became more like real music (isn't it what we all want). My McIntosh witch I used before simply could not keep up with Cybers. Recently I replace original tubes with NOS tubes from Amperex 6922 white label made in Holland(1960)& Tungsol 5687 from early 1960's , also replaced stock EL34 with JJ blue new line. After installing new tubes sound became more sweeter , even better sound stage then before , very tree dimensional and better resolucion . About two months ago I purchase Vandersteen Quatro witch in my humble opinion are the best speakers for the money (I was also looking at Opera M-15 but they are to big for my New York apartment). I was a little concern about Cyber 800 driving new speakers at first , because they are only 78 watts per channel. My worries quickly disappear . Cybers had no problems driving Vandys. The 300 watts amp. ( driving bass units ) build in Vandys properly helped. If you are looking for natural, musical and universal amp( accepts EL34,KT88 and 6550's witch will bring it to 110 watts per channel ) look no farther. Take my word for it. You will save a large amount of money & you will be happy for a long time.