I ordered a 5Y3GT "SOVT" from AES, for my National RBL-6. =20 I'm sure it was there in the fine print in the catalog, but I didn't = expect a "New Old Stock" tube. It says "made in USSR, which makes it at = least 10 years old, I guess. My bad. Anyhow, does anyone have experience with the Russian-made tubes? Are = they known for high quality and mean time between failure? - Fred M. KA1DGL