Andy's car has spoiled you IMHO

. A lovely 944S that has to be said.
Call me cynical, but many M030 setups for sale now are quite tired if they are original, and those which are not so bad (refurbs) command strong money secondhand from what I have seen (although competitive to the options listed below). I would say to drive 944s on different/fresh setups to get an idea of where you want to be (and to get an idea of whether you believe it is worth the outlay), but this is not always easy.
I believe you can still get the stock front dampers with cases at around £230 each, plus the rears at a shade over £60 a corner. If you do not mind cutting the front struts up I would be tempted with the Bilstein B6 dampers (I have yet to be disappointed with these on a car) at a cost of £122 a leg up front, along with £133 for each rear damper from Design 911. The Spax kit looks great value as you have seen, although the results seem to be varied from the reports people have mentioned.
If you decide to lower, it may be worth considering a coilover set with the Spax items being the cheapest as said (although with variable results) along with the Gaz Gold kit (but this has gone up in price recently to over a shade above £800!). Springs seem to be around £150 for a pair.
968 Castor mounts IMO are worth the outlay, giving slightly sharper steering along with keeping the front wheels in check in the case of the larger 17" wheels (there is a Porsche Technical service bulletin outlining this). TR7V8's offer is one I would consider. If the very front wishbone bushes are fine I would be tempted to leave them (they seem to last in almost geologicial time it seems (when I changed my arms on the old S2 for new items, the bushes were fine much to my surprise, a bit a of a testament if you ask me!).
Steering UJ sounds like a candidate (was this down as an advisory at all for the last MOT?) and it is easy to check. Another area I would look at is your ARB mounts (these can snap, and the bushes can expand with oil or simply wear out over time; the drop link bushes at the wishbone can fall victim to wear as well). Some may disagree here, but whilst the Porsche items are of a good quality from the dealer (and cheap) I would go Poly for the ARB bushes, especially with how fun oil changes can become in addition to Poly bushes seeming to be resistant to oil (Superflex and Powerflex seem to be good bushes for here).
One more thing (forgive me for sounding like an old record), I would be tempted to shell out for a full geometry setup, to really get the best. I appeciate I am on some pricey suspension, but the difference between this car and my old S2 is a night and day difference (no iffy rear end, and if I am honest, my S2 seemed was relatively firm with a little more wallow than this one (well, it is near non existant in the Turbo!). At the time my S2 seemed to handle significantly better the other tired 944s I saw for sale. I really was pleasantly surprised with this car, and could finally appreciate the suspension work (although it would have cost a small fortune on my old S2 I reckon).
Oh, and sorry for this marathon of a post

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