A very reliable synth, any faults that do occur tend to be subtle and tricky to diagnose, there is no specific weakness in the instrument that requires special attention.
Backup batteries will die, that is inevitable with time, sometimes the front panel switches will wear out.
The keyboard itself uses high quality sprung steel springs and metal contacts so does not suffer from the rubber membrane switch problems that many other synths of the era do.
There is a special edition EPROM for the operating system which corrects the failings of the early MIDI spec and brings the early DX7 some way into the modern world.
We have only seen one of these so far, and it was a 2 person lift, (at least to safely manoeuver it around).
A triumph of plywood over metal casings, this machine has wood so thick you could sail it at sea.
It is in essence half of a CS80, 8 voices but only one oscillator per voice. It does however use the same voice cards as the CS80. It also has the ribbon controller from its bigger sibling, and an optical pressure sensor which is channel rather than poly pressure like its big brother.