Hilde45,
I really can’t say anything about the power amps. When I demoed the Cornwall IV it was using a MAC7200 oddly the same setup at two different shops. I don’t remember what the forte was using as I was really shopping the Cornwall/La Scala.
when I demoed the La Scala (current model) I heard it on the MAC7200 and MC275 in the same room as the Cornwall IV. The tube sound was very noticeable in back to back A/B but the MC275 is a pretty high power tube amp with way more than enough power, which still had good dynamics. I stay away from tubes because I hate buying them and worrying about their life, I like the sound though.
it was just demos, so only a few hours, longterm users can give you more insight for sure. I did listen to the systems a number of times as it is my local shop I normally buy from. We moved the Cornwalls all around the room, close to the wall, well into the room, in the corners, etc, I like the typical audiophile isosceles triangle setup the best, toed towards the shoulders.