I've run the new sensor KT66 tubes in my Edana and they are basically a 6L6 with thicker and larger glass tubes. Compared to the other KT66 tubes I've used, it sounded kind of wrong. Midrange wasn't as present. Seemed to want to compress a bit when cranked instead of distorting. I didn't like them really.
There's my 'bogus answer' for ya.