Just bought these Valve Art KT-66 tubes to try and also to have as spares. Just want to let everyone know that they sound fantastic and just as good as the Tung Sol tubes that I currently have in my 2466. There is however one difference with these I did not expect. These Valve Art KT66 tubes make my 2466 noticably louder, (this is a good thing) Plugged these in and right away I could tell I had more power. Don't know if that is normal or not because I have changed many power valves before in amps and never really noticed the change in volume with the amp.
Anyways if you are looking for a replacment KT66 I can vouch for the quality of these.