I've recently acquired a beaten up Korg DW8000 (it doesn't look as good as the one in the pic here...), a synth which I have previously owned two of, and missed each time it was sold.
It has probably been gigged a lot, and now had a problem with unresponsive switches, noisy volume slider with the sound cutting out, some unresponsive keys and hanging notes. Ann's son, Liam (the brains behind the MIDI Controllers) replaced all 22 new switches and volume control, and I got a new OS chip. After spending some time with the keyboard mechanism I just about solved the unresponsive keys, though sometimes they need an initial press to 'wake them up' but the synth otherwise is fully working and sounding great. Some of the keys are damaged but I'll probably live with them.
All this leads to us now supplying dust covers for this synth (and the identically shaped DW6000), see here:
I'll take some pics of mine with the cover soon.