I concur with Mr. Deckert.
I have bought alot of expensive tubes only leaving my wallet thinner in the long run: NOS Mullard EL84s, Bugle Boy 6DJ8s, NOS 6922s.
You know what sounds best to my ears and most others who have heard my amp (Hornfest '05 & '06 among other local gatherings): The stock 6N1P and a matched pair of SV83s.
My amp is very warm...
FWIW I do not post too much anymore.
Why? I'm happy and not looking to roll equipment.
Most recordings sound live on my system and that was my entire goal.

Some may call is @ss kissing, but Decware was an awakening for me, hearing things and experiencing recordings like I never had before. Let alone at a price one could call ridiculously low.
Couple this with a fine single driver setup and you're done.