entierly agree with ^^
its starting to happen with the S2's now (not so much the later ones ...most seem to still have them to use) - and some bits like trim still cant be got in decent quality or correct like the S1 ...untill there worth similar amounts i doubt it will be , same with the stage 1 no one will pay £500 for a trim set like on a S1 when the finished vehicle is worth only £3000 ish as opposed to £10000, probably be 10 Yrs or so on the S3's i think (there's still allot about.....in 10yrs id bet they will be getting a bit thin on the ground), even rare ones like the V8's still aren't regarded that much as collectable that ive seen, over here anyway ...and im not sure they ever will be in the same class as a S1 , from a collectable point of view, thus the specialist market probably wont cater for them in the same way.
