ORIGINAL: Diver944
Coming back on topic and in an effort to help Copperman.........
I've driven a lot of the options available (on my own cars and other peoples) and have jotted down a few notes.
My S2 had new factory Sachs shocks all round and it transformed the car into a tighter ride but with a lot more comfort than the 150k mile units they replaced
My Turbo had its M030 shocks rebuilt and once again it was improved in agility as well as comfort. These shocks are a lot stiffer than S2 units and do not absorb bumps on poor surfaces but are great on smooth tracks with less lean and pitching under braking/acceleration
Dave Malings Turbo (now Jon Traslers) had Leda Coilovers all round and when set to full stiff was excruciating on the road, very crashy and hardly any damping, but on a circuit it was fantastic - much better than M030 with very little lean or pitching
Fen and MarkKs Turbo with KWv3 was much firmer than M030 but less firm than the Leda. However it betters them all in every respect - nicely damped for the road, very comfortable over bumps yet much less roll than any of them. On a smooth track it really is the best compromise until you get to out and out race suspension. At Silverstone in Fens car he could really attack the sharp sawtooth kerbs at Abbey, yet my M030 equipped car would be thrown all over the place on the same kerbs - an excellent demonstration of the KWv3 high speed bypass valve [

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MarkKs race car on Gaz remote reservoirs is the firmest, stiffest 944 I've driven on the road and I have to say I was surprised how it coped with road surfaces. It was more damped than the Leda and the M030 but obviously nowhere near as comfortable as the KWv3 and the standard Sachs. On track it is simply the sharpest, stiffest, best handling 944 I have been in to date (As you would expect for full on race suspension)
Copperman if you intend to do only a few track days then I fully recommend you replace yours with stock Sachs struts and new rubber bushes all round. You won't compromise your road comfort yet it will still handle a country mile better than your old worn out units. If you want a slight upgrade in stiffness go for the Koni inserts as Oli has already illustrated