Guys is simple:
Vsc sport increase the limit of when the automatics step in and try to stop your rear to slide.
Everything off is everything off.
I suggest:
Rain: leave everything on unless you are really really good. I have gone in vsc sport mode once when it was really wet and rainy... Well at one roundabout I decided to see how much it would slide... It was not a progressive slide, one second I was straight half a second later I was with the rear by my side ahahah
I was ready for it so I just slided for half the roundabout and then continue on my way... But was brutal if you compare to how this car normally start sliding.
With rain for me is: all on. It's too stressful to be ready every turn or acceleration you do to keep the car straight.
Road I don't know:
Vsc sport
Road I'm
Familiar with: all off
I agree with who say that VSC is shit... It's true. It try to counteract over steering and sliding so hard that usually it just makes the car slide on the opposite direction and it does it in a brutal way, it helps only if you start sliding and you didn't want to do it.
Little hint: be careful on tight corner and not good pavement or slightly wet pavement. I have Michelin alpin as winter tyres but I had few very bad under steering experience on tight corner, I know it's because I was not accelerating enough but the traction was cutting the power and the car instead of turning and sliding just went straight and I shit my pants twice ahaha
it was my mistake for sure, just reporting my experience.