Anyway, as far as i know if your getting 80 quid emz's they are good for metal. My friend upgraded to them. He said they are the best pick ups. I'm guessing they are good for mettalica style guitar playing becuase that what he likes.I dont think you will need knew knobs and switches though but you will need to change the electronics. They will do that for you when you get them changed though.
By virtue of their electrical properties, tubes generate a special waveform when they're saturated, which is why tube engineering has tremendous tonal advantages over solid state or DSP solutions, particularly for crunch and lead sounds. Tubes enter the saturation zone gradually or softly, which lends tube-driven tone its trademark yet totally unique character.