Are EL34 based amps more musical than KT series based ? Or it's purely a matter of design?

IF a VPI magic brick on the output xformer significantly alters the sound for the better, you know they skimped….. 

RM-9 wrings quite a bit out of EL-34 but Roger was a genius… Like Gordon Gow and the 6L6 MC240… but really no meaningful conversation is possible without also considering the massively important imo ….output transformers….