I wouldn't say 0wXX oils are a waste, they do have their advantages, but they are certainly not a must in cold climates, as some on here make it ought to be.
Somebody asked "What happens when it's -40 and all the plug-ins are taken so you can't plug in your block heater?"
If you have a healthy battery, NOTHING! You may have to crank a second or two longer on a 5wXX oil and that's about it.