j-wall I bought them in 2010. In the third year the power ampl failed (one output was not audible). After multiple communications with Mr. Deletraz (very nice man), I sent the amp to Switzerland. Returned within a month. The fault had been fixed. I sold the amp and the new owner reported another malfunction (one eye not lighting up properly). I don't know what he did next. That's about the amplifier. Let's go to the preamplifier. Within a year of buying it, I found that the black rubbers surrounding the two potentiometers had started to polymerize (!!!!!) I was shocked as soon as I saw them. From that day on, I was careful when I needed to rotate a potentiometer, not to touch the rubbers, lest they be cut (!!!!!!!!). Unacceptable for a machine worth €20,000 (when I bought it). As for the audio quality, they sound great! but no better than the preamplifier -power combo I use today even though they cost less than half what the darts were! That's all.
