Pindac, I see your point, but on the other hand, what is the value of your post if no pertinent information is given that would permit anyone else to benefit from your knowledge and experience? If you want to honor the privacy of the maker, you might find some other way to indicate the name of the business. Like "X makes very nice preamplifiers to order, often using the tubes in question". I just can't see how that could cause problems for the manufacturer, other than an overload of orders.
ditusa, Good call on the Atma-sphere MP3; I should have thought of them myself. I own an MP1 and like it a lot, obviously.