Even though I own a 260, I still feel the 240s should go for slightly more as they are the origin of the species....
S30-S, S30, PS30, PS30-SB, HS30-U, HS30, HLS30-U and HLS30 are "the origin of the species", and even
they have their own sub-variants.
All were conceived, designed, engineered and productionised at the same time. All share their DNA, and all share
design concessions. Put simply, they were as they were because they all came into existence
together as a family of sub variants in
the S30-series Z model range. Like octuplets.
The terms '240Z' and '260Z' mean little on their own.
What 240Z? What market? what sub variant? What production date? What 260Z? etc etc.
I think this is the kind of thing that (interested) first-gen Z owners really ought to talk about more.