Well, realistically, if NOS tubes get 5000-10000 hours each, I'll probably only need to buy between 10-15 sets in my lifetime before I either die or loss my hearing. The next generation is screwed.
The stock GE's are the worst ones I've heard by a longshot. Totally lacking in detail, inconsistant from listen to listen, they ran about twice as hot as all the older tubes I've tried, crackling in the upper mids...good riddance! I think the Schiit guys are hurting their own product packing those in. I hear they are generally considered better than the stock JJ's too.
But I do wonder...would it really be that hard for someone to make a reliable audiophile grade new tube? Obviously the demand is there.