Excellent all rounder
Just bought a quad set of matched Preferred Series EL34 for my stereo VTL ST85 amplifier, to replace the stock Electro Harmonix. Now, don't get me wrong, the EH is a great tube, solid, reliable. But I think the Preferred is a notch above the EH - impressive deep end, very nice midrange and an upper end which is just right without being too edgy. Highly recommended.