I've been hanging around these amp pages now for a couple of years and I've come to notice that a couple of the good folk that are into the D type amps such as TAG, Traviswalk and Sfarnell amongst others seem to not be content with owning just one D type amp but have several in their collection. I am curious as to why that is. Surely there can't be a phenomenal difference in tone between amps of that genre I would have thought that you would just keep the one that you like best and sell the others.