To answer my own question for others information,
the tubes work perfectly, no red plating and the sound is un believable!! the stock tubes wouldn't play very loud without losing detail,
these are supposed to be less powerful ,but you can't tell by listening. I now understand what the room being pressurized is, there is just so much weight,
I know a lot of this is due to the combination of my Zu speakers and the amp. If you want to try a 845 based amp I couldn't recommend the Line Magnetic 518ia any more enthusiastically!!