I think it depends on the area as well. Are you in the middle of the city of Milwaukee that gets hundreds of 911 calls a day and does not have the manpower or resources to even respond? Then no, I probably wouldn't call.
Would I do it in my population 7000 little village that is 3 square miles and I know the cops do pretty much nothing all day and they get maybe 4-5 911 calls a day? (I can rip on the cops cause I work so closely with them)
Most definately. (but I wouldn't cause I have non emergency #s for everyone around her in my phone. But if I didn't I'd call 911)
I think it depends on where I am, how "emergent" I feel it is, and other circumstances. However I work for emergency services so that sckews my perspective some as I've seen the 911 abuse. One person commented that people call 911 for such stupid stuff, why not this? It's important. I agree. But that doesn't change the fact that people call 911 for stupid things and now you have these unrestrained children calls in addition to the stupid calls clogging the lines even more.
When I lived in a smaller town near Melizard I did call 911 once and couldn't get through (they had 3 lines at the time, technology has changed since then allowing 911 calls to go to other cities instead but still increases response times) and it was very very scary. It took 3 attempts for me to get through and that was precious time wasted. Since then I always try to encourage people to not call unless absolutely necessary. Because that could be the split second you call, the dummy who is mad at mcdonalds calls, the lady who wants the address to the firehouse calls, but also the split second the wife tries to call 911 because her husbands heart stopped beating. And she may not be able to get through. That always scares me.
So having a non emergency # programmed into your phone is the best bet. If not, make the decision if if its important enough to use a 911 line for. Only you know if the situation at that moment warrants it