Wow, I'm seriously chuffed. This all started a bit as a nightmare, ordered this rather expensive quad of EL84CZs from TAD (75 EUR the quad and lots of promise in the advert).
Then when I received them, I bent a pin of one of the tubes and it broke. Now it was great they sent me for free a replacement tube with identical values to the other 3 intact ones and it arrived today, so I put them into my Budda Superdrive 30.
AWESOME! What a change, it's suddenly so clear, big, transparent, harmonic, endless sustain and feedback are no problem, gain to max still sounds great. Wow guess this is gonna get a good beating up over the coming weeks.
Already played 3 of my BKP equipped quitars through it and each of them sounds awesome. This really transformed it into a completely "new" amp.
Recommend these tubes and TAD service to anyone who has an EL84 amp.