I just tried my first NOS tubes this morning. Frustrated that my thrown-together bedroom system sounded more musical than my big rig, I remembered I had bought a couple Sylvania 6SN7s at a flea market a couple years ago. When I had gotten home, I tried them out but wans't impressed (I thought 1 didn't work - maybe I threw that one out). So I plugged them into the most critical spots on my Atma-Spheres and was very pleasanlty surprised that they both worked, and the sound was much improved over the EH I had in there. Perhaps i had been too tired the first time I tried them (if you've ever been to Brimfield antiques flea market, you'll understnad it's an overwhelming experience). I will say, though, that when I first tried the new TungSol re-issues, they had a dynamic strength that I had never heard before in my system. Drums sounded fantastic. Thisw quality was short lived, though, as the tubes broke in and ended up sounding just like the electro harmonix.