For day-to-day use, I've had great luck with the large bottle Sovtek EL-34s. But for delicacy, it would be hard to beat the small bottle Seimens NOS EL 34s, if you can find them. I also have used the big GE 6CA7s for day to day listening, and they were very reliable. I don't know what's available now, since I bought enough Sovteks to last me a while, but I'm sure some of the other A'goners can help you with the newest hot tubes.
Good Luck,
Ed
Good Luck,
Ed