Have you given up your Land Line phone for a Cell Phone ?

Many people no longer have Land Line Phones.
My Land Line phone gives Emergency Services my Phone Number in the event I am cut off during an emergency. My Cell phone does not ofter this feature. I do not think most do. This concerns me and I am keeping my land line.
The INTERNET phones do not offer this feature.
On 911 all Cell Phones in NYC were deactivated . My Son was at school. Using a Land Line I had to hit flash more than ten times to call his school.
Do you think it wise to be without a Land Line ?