Just been reading this for a few days, so i thought ide chip in my 2pth...
Ive had both the KW v3 and the Gaz [EMC race spec], kit on my cars.
The KWv3 was first fitted to my S2 then to my 968 sport.
All over aprox 3-4 year period.
It worked great , i travelled [drove the car] to and from many of the uk tracks and had some fab times on circuit.
The car ran on Dunlop D01J track tyres so had lots of grip.
The KW was great, but as i progressed up the "tallent" ladder and found myself pushing harder and faster, i found the KW,s limits.
Thats why i bought some of the GAZ kit. It is more race focused, but is definately stiffer than the KW.
also its not as durable,
Its not as resistant to our salty winter roads...
Mine didnt need a rebuild but ive know a lot that have....
They leak around the piston seals, usually the front passenger side , must be something to do with the cornering forces and direction of our uk tracks...
So, in conclusion.
If your driving your car to and from the track, get the KWv3, if trailering any of the other kit, be it GAZ , AST, etc etc...
Hope this is helpfull...[

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