I think I ought to expand my answer a bit...
I have occasionally turned mine off when in an exploratory driving mode, mostly to see what the native characteristics of the car are, or possibly to have the fun that the VSA has censored. I have done 60,000 miles in a 968CS, so am familiar with the basic, raw, sideways round every roundabout concept...
But I leave it on because in all
other modes of driving, it does nothing at all. So it doesn't improve my experience when driving by turning it off. You have to bear in mind that some people might not really understand what's going on here and may read this and turn their VSA off thinking it may make the car better in normal use.
To clarify, the VSA only does something in two situations:
- When you are deliberately sliding the car. Here it inhibits your fun.
- In the split second just as you are about to crash. Here it often stops the crash, and subsequent injury or death.
I spent a bit of time messing around with the VSA in the snow this winter (trying to fool it, and seeing how well it coped with idiot moves like braking hard round corners) and it was excellent. It deliberately allowed power and braking slip at low speeds, and did a great job of trying to stop a spin.
So, unless you are hooning around in a controlled environment, it has to be better off switched on, along with airbags enabled and seat belts on.