about the kt 120 tube

I also think it's strange the Chinese haven't come up with a KT120 type, since the design is a gigantic (really...amazing) home run in tubeland, and has been around for a few years. I also would have expected some "gold pin extra cool with fancy writing on it" version to satisfy the hoards of people who need more expensive things. I did "drop in" a set of 120s in an otherwise 6550/KT88 Jolida (after being told by Jolida it wouldn't destroy the amp). They sound great and I've found nothing to make 'em drop out.

that kt 150 tube looks real nice. let me guess?? 200wpc a pair in push-pull circuit. i can see a kt 180 and kt 200 tube in the works

The reason the Chinese haven't copied the Russians might have something to do with their raw materials and their technology. They are behind the Russians on both. After the issues with the first 6550's out of China many years ago, I am wary of them and therefore stay away from them. That being said, the only Chinese tubes I found to be exceptionally good were the EL-34 Treasures. That's about it.

I'm using a matched pair of "tubestore" Preferred 7025s that they source from China and they're great.

I have not tried those. I currently use the JJ ECC803S. I find it to be very quiet and good sounding. I know some people have had issues with them. So far no issues...