They are as stiff as you want them.
Standard height they are just highly improved on stock VW.
Slight lowering and they stiffen up the ride, but not bone shaking.
Slam on lowest setting like mine and they not only look awesome, they are very stiff. Mine is a hard ride, but not so much so, that your fillings fall out. Handling is much improved over stock, but to get the full package, you will need uprated ARBs, though not essential.
This is mine on lowest setting to give you an idea just how good they can look over stock height.
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