Yes they are!
I can't go back now, snow is 6-10" to get to my house and they work a treat.
Even on the main roads where folks are driving like they have trays of eggs in the boot, I'm able to drive normally.
I did some test driving/emergency stops to find the limits of the tyres in different conditions so, I have a better understanding of them (while I was on my own and no other cars around) still, it’s not a license to go mad or drive fast, remember a lot of folks can’t stop that quick and you will be caught out yourself! as they do have their limits but, I feel much safer driving with them on.
If winters continue like this, it should be law that you have to fit them…..the number of people who you can see are in trouble with traction, it’s just dangerous! for them an others.
NOTE: This is in a family car, not the supra.