Time to get the hackbike (still has the Marathon Winter studded tyres on from last year) out of the shed. 
How did you find those tyres if you had to ride on normal road surfaces? I might invest.
Fine, you're supposed to wear them in on normal roads for 50km before real use so I commuted on them for a couple of days. Only added a few minutes to my 26 minute commute.
Pumped up to the top end of the recommended pressure the studs don't really make contact with the road on the straight (you'll definitely notice them when cornering though), just a gentle hum. When it snows, or there's ice, you can let the tyres down a bit to make them much more effective.
They're not something you'd use all year round though. Just when there's a threat of ice/snow.
My problem is limited storage. I have only have one bike in use at a time, swapping over bikes takes a considerable time faffing in the shed/bike-locker with big locks in the garden in the dark, etc. So I want to limit the number of times I swap.
Next week is a easy decision though, it's going to be hitting -10
oC air temp some days. Plenty of chance of ice on corners...
