Basically if you run your car below zero (c) use something else.
I got caught when winter came early, my car was sat at work for a few days when I returned to pick it up. Was about - 5c and engine clattered away and oil pressure light remained on for about 10 seconds.
I did an oil change in my garage a few days later and the oil drained like tar, all congealed and separated. My garage heater had quit so again it was around zero when I did this.
For an advertised 8w oil it's way too thick for me. Probably okay for warmer climates but certainly not year round use for me.
I went to redline 5w40 and she likes it alot better, alot cheaper, good start up and no noises = win win