I have made a decision that in the same way I only play Les Paul guitars, I am only going to play Marshall amps. With my Ultimate Attenuator and my 68 50 watt plexi, I can get the great Marshall tones I always dreamed of at the lower volumes I tend to play at. And I realize that it's the Marshall tone I want. There are other great tones out there but I want MARSHALL. Since I'll have funds from selling my vintage AC-30, I want to get either an 18 watter or JTM45 as my next Marshall style amp. I don't need gigging headroom. I have the plexi for that. I'm just thinking what would be best as a 2nd flavor of Marshall? My gut feel is JTM45 as being more classic Marshall tone. And I've never tried KT66's so that could be cool. I have my Ultimate Attenuator so roaring at low volumes is no issue. Is there any special reason to try an 18 watter over the JTM45?