Your guess is as good as mine.
However, Quicksilver and MDD G4 Dual processor computers STILL go for over $600 US on Ebay.
It is quite possible that the older Dual G5 systems will hold some value. You will NEVER get a full ROI on a used computer, unless it is a TRUE one off, and everyone wants it.
I think only the first LISA comptuers still take almost as much money as they cost new, but situations like that are super rare.