Had a set of french made mazda 6v6's in my rivera designed ChampII and one finally fried last night. I have a spare set of GE's that I put in and the tone is quite a bit different but not in a bad way. The bass is still nice and tight and holds together but the highs are a touch more harsh than the mazdas. The breakup comes quicker and has more hair on it. They seem more touch senitive also. Even got some feedback goin with them. I need to get the amp biased also but so far the General Electrics are going to be fine. I do have 1 RCA new in the box left but I'm not sure where and if I can afford another one LOL. What is your favorite 6v6gt, new or old?