Someone above made a Harley Davidson reference, and it fits well in this discussion. The best tube amps that ever existed are being made today, but they still include the same important electrical physics element, inherent distortion. Currently Harley has to be careful not to engineer out the trademark sound of the past engines just like the makers of tube amps want to make all parts of the amps better with what engineers have learned, but still using the tube design factor. Tube amps are very highly refined today with better transformers and more capability than ever, but just the fact that they are tube amps, and will have ~.5% distortion to start, and this distortion seems to add a harmonic that is pleasing to human ears still makes them desirable and makes the current offerings from all over the cost spectrum alluring to audio lovers. I have no way to state to anyone what the best amp from past or present might be, but I can admit that I'm still interested in a MC275, and even some of the offerings from lower end players such as Monoprice and similar to play with. While I look at some vintage pieces with nostalgia and desire, knowledge and common sense tells me to buy something current with all the improvements.
