Cars of this age are as much dependent on the quality of the restoration as of the original engineering...
That said, the hydropneumatic suspension is not very ddifficult to keep in good order. The Maserati/Citroen engine and the engine bay are...
I've driven one (very nice navy Blue). Very disappointed. Having tried a Merak and several Goddesses, it's doesn't measure up to either (plus I hate the Citroen "mushroom" brake.
That said. I adore these cars. A wonderful concept that is utterly lost now