NOS or used, what should I choose?

• "Used" tubes are expected to be any cheaper
• NOS tubes - out of their sealed boxes - can have an anode current from like 80% to 120%. So there is nothing wrong with a "used" tube which is providing the same anode current, from 80% to 120%.
• Used tubes have already proven their reliability under real-life conditions !!! Especially if they were removed from military devices or scientific applications. This is why such sources are our first choice.
• It is a proven fact that (vintage) military and scientific equipment most likely had HIGHEST QUALITY tubes, which are - however - better quality than the consumer tubes that are so frequently used in hifi-equipment.
• „Used“ quality tubes - if tested with ROETEST under datasheet conditions - are less likely to fail.
• "Used" tubes are already „burned in“. You plug them in, and they may sound wonderful - from the very first second on. Whereas some new tubes need hundreds of hours to reach their „full sound“. Explanation: Tubes need time to adjust themselves (german: Einspielzeit). Speaking of any timespan between a couple of days to several months. This does not belong to used tubes though... or atleast not in such a matter.
• We would always prefer a tested "used" tube over an untested NOS tube which is still sealed in it's box.
• If you buy a sealed NOS tube you cannot feel certain that it's fully working. That's why we NEVER offer sealed boxes of ECC88 tubes. In fact we open up each NOS box and test the tube before advertising on our website. Makes sense. Some people think that a „tested“ tube is not NOS anymore, because it was "used once" (yes, during the test). Well,.. .go figure.