I guess I like to know the safe limits of my vehicle - took a pretty sharp 90 degree turn last Friday night and triggered the VSC - several short loud beeps indicated that it had kicked in - worked pretty well. Toyota did a great job on this.
I'll engage mine pretty frequently. A few times per week. Here in Phoenix some streets have a lot of grit/gravel on them, so when I pull quickly out of a driveway ahead of an oncoming car, I'll feel it kick it, see the flashing indicator light, but I hear no beep. Then again, I disabled my reverse beep, perhaps this disabled this beep as well.
Light flashing w/o the beep is traction control and/or ABS. VSC only kicks in when your vehicle is (or will be) skidding - i.e. getting sideways or plowing through a corner. So for review: 1. Braking hard - skid light comes on - that indicates ABS has done it's job. 2. Accelerating and wheels spin more than one time - skid light comes on to indicate traction control has taken away some of your fun. I've noticed that if they slip only once and power is cut, the light doesn't come on. 3. Getting crazy in corners, or during an accident avoidance maneuver, light flashes and car chimes, VSC has kicked in and possibly prevented an accident. hope this helps, -Rick