Really worth while if you are doing a good few miles.
Fit them every winter and you can defo tell the difference, be passing people on hills that are stuck and i just toodle by.
I drive between Thurso near John O Groats to Aberdeen and i have never been stuck in a winter up there yet with traction loss.
I use Gislaved Nordfrosts, usually fit them between Nov until Apr each year and get roughly 12k out a front set on my astra van.
They are also quite good as a wet tyre.
Once you have tried winter tyres you will honestly think to your self why hadn't i done this before, peace of mind if you have a bad spell.