Although I've heard a lot of flack about the 4000/II, I have to say that mine has been trouble free until recently, left channel dropout with autocorrelator engaged. A lot has to do with the internal
architecture, backplane with daughtercards. The trouble comes from the card slots and ancient (sometimes sloppy...) soldering. They crack!
I think they're good overall, but what you may get will be "iffy" as to proper functioning from those issues. Even if you get a good one, with time it may crap out. I lucked out on mine! But by ALL means,
STAY AWAY FROM THE ONES WITH THE JOYSTICK!