Can't say they have stood the test of time because one has been in my system for 14 months and the other only 6. But I have been looking for something this good and satisfying for a long long time. The most satisfying components are my TAD 2404 speakers - to my ears they are accurate, musical and detailed. And the second most satisfying is my Kinoshita HQS2500UPM power amp. Before the Kinoshita, I had not had a transistor amp for 20 years and the last amps I had were Audion silver transformered black gated prototypes built around the VV52B tube. They were great single-ended mono blocks but to my very great surprise, bettered in all departments by the Kinoshita. Since I have been blessed with these two items I listen nearly every day.
Happy listening!
Happy listening!