I own a CAT for about 6 yrs now, and i heartily agree with all comments mentioned by others. If it is the music your after, and all the emotions it may give you, the CAT will deliver, and will be a supreme partner. I have mine upgraded to mk3 status recently, and it was bettered in many ways, after spoken to many other CAT owners, the mk3 versus Ultimate is about preferences really. I know of a friend who owns both, and he doesn't want to choose between... the Ultimate is said to be a bit more relaxed and easy in presentation, the mk3 with a bit more liveliness and attack.. very subtile though. I have a word of caution regarding the people who 'throw' in all different [nos] tubes, in search of even better sound.. The v6 and v7 tubes use 6922 sovteks, and are very very closely matched by Ken Stevens, and with strict reason. As the service manual clearly states, you may not use the 6dj8, [at v6 v7]. Now my CAT has been serviced for many time by the tech-rep in my country, and with all the tube trying and changing I did, the FET's have blown up many times.. although this didnt stop the music playing, it ruined the CAT sound.. i have only recently been aware of this, since my tech-rep told me about this in detail.. so, if you don't happen to have a tube tester yourself, or somebody doing the tube matching, AND KNOWING ALL THE PARAMETERS ON THIS FOR V6 V7, but instead you are just trying whatever nos you can lay your hands on, you are JUST PLAYING AROUND, and you ARE IN RISK of blowing FET's everywhere ![yes up into the power supply!] The only one I would make a call is Ken Stevens himself, or Kevin Deal from Upscale audio. ofcourse i know that the NOS philipse's and Amperexe's DO sound better than the Sovteks.. but if you do all parameters well for matching THESE 6922's you will end up needing hundreds of tubes to come up with good pairs, and there are not many Amperex 6922 left these day's! [that's why Upscale charges astronomical prices..] so, you may think it your way,[and that's what I used to do] .. But I learnt my lesson now, and stick to Ken's advise, [through my tech rep] Mind you, I am also buying all sorts of 'NOS 6922's still, but I let em carefully check first, before maybe using in my CAT. we have NOT found any NOS which were up to standard..[and i live in the land of philips and Amperex !] If you have been putting in all sorts of NOS at v6 v7, and are in doubt after reading my note, pls contact your CAT representative, or Kevin at Upscale, it is worth the check. One happy Cat owner, may the music touch you !