"Ray O" wrote in news:o8ydnbSD7tyDINbanZ2dnUVZ snipped-for-privacy@comcast.com:
In practice though, the ABS-based system actually works fairly well from what I've seen. It's unusual for all four tires (or even both on the same axle) to be low enough at the same time, sufficient to pose a safety hazard.
And nobody is going to benefit from any system if they ignore the light. How many people ignore their Check Engine light?
Plus they severely limit your choice of wheels, which is a major disadvantage in the snow belt.