I've been playing with the E530 for the last few days and I have to admit, I wish I'd bought it sooner. Playing with it somehow feels particularly fluid and easy, I can't quite describe it… the saturation is just somehow exceptionally satisfying. In terms of tightness, I could most likely manage without an additional overdrive, but I still prefer it with the good old Tube Screamer. However, I find the labeling of the EQ section as low and high mids somewhat misleading. While the low mids are set at approx. 500 Hz, the high mids simply correspond to the regular treble control of other amps. According to the instructions, the actual treble control, on the other hand, is intended to compensate for the possible lack of a presence control on some power amps. Anyway, fantastic device! ENGL have got it right.