Another curmudgeon / "Get off my lawn!" thread. I was just looking at today's offerings of (overpriced) 6V6 tubes on eBay. Oh, wait. I see why they're expensive. Many of them sound "amazing" while some of them exhibit a convergence of "amazing" tone and exceeding scarcity defined as "rare". Methinks someone is blowin' smoke. My girlfriend the scientist walked me through the Six Sigma formula that establishes a bell shaped curve. It's supposed to encapsulate most of the objects that exhibit "good" characteristics in the fat part of the curve with a very few objects that "suck" or are "exceptional" as outliers. I'm accumulating more tubes that suck compared to "amazing" tubes I'm hoarding. Suck tubes get a big "X" in permanent marker. In any functional quality program you're supposed to identify and segregate defective parts. Been there, done that. The vast majority are acceptable if not exceptional.