I used the WAZE app during an ice storm in KY (or TN) that brought the Interstate to a stand still. It immediately routed me to a side road that paralleled the Interstate and brought me back on where the traffic cleared. It was about 2 miles out of the way but got kept me moving. You could see the Interstate at many points along the route and no one was going anywhere.
I don't like that it eats up data on my phone so I usually run a standard GPS but this is the second time I have used it when traffic was bad and in both cases it saved me time and gas with the new route.
Thanks for the information about being able to turn off the obnoxious warnings. I will look into getting that accomplish the next time I open it up.