People sure have different ears, that's for sure. I had a '93 Clubman at the same time my roommate had a KT45 and they sounded NOTHING alike. I have a Ghia now and have owned a Lightning, and again neither sounded alike to me.The reason I did it is because many of their amp designs are kind of similar, Clubman = KT45, Invasion = DC30, Lightening = Carmen Ghia. Not exact but pretty close in many ways. They are not 2x the price though, a Clubman new is $2200, a KT45 is probably around $1400.
I think it's pretty pointless to say one of these brands is "better" than the other. I have owned and enjoy both. I still have my Ghia. Have sold my Matchless stuff. That's just the side of the fence I'm on right now and it's serving me well. I'll bet money that I'll own another Matchless at some point though.