Leben CS600 required tubes

I've got Mullard EL34's (produced in Russia by New Sensor) in mine now and they sound great. I didn't like the Russian NOS 6P3S-E (I only tried one plate voltage...) or the stock 6L6GC Sovtek's (altho I liked them better'n then the 6P3S-E's).

Thinking about trying the Genalex Gold Lion KT-88 reissues next....