I ride all the time, for most of the winter I didn't have the money of studs, I have slicks on. When I did get the studs they were great, I live outside of the city so the bike paths are not de-snow/ice, ect. When in the city they is still ice covered roads and sidewalks, they have saved me a fall. I would get them, one they last a LONG time, so when you pick them, get one you like, they last 6 to 10 years.

Weather you need studded tyres really depends on the conditions you are likely to face. Around here we get a lot of ice on the roads, especially when the temperature is hovering around the Zero degrees celcius. Then we have freezing temperatures during the night and a thaw during the day. That, in my experience, causes the worst conditions in reagard to ice. It's actually funny that the colder it gets, the less you need studded tyres, in my experience.
I would also say that if you are going to buy studded tyres, the W104 aren't really up to it. The problem with the W104 is that they only have studs in the center of the tread, so if you lean into a curve you might well loose traction - right when you need it most. The Hakkapellita 240 was reccomended to me by the people at my local mtb club who have been commuting by bike for years over the heavier 296.
Just be careful that your bike has wnough clearance for the buildup of snow on the tyre. I know at least one person who has been having problems with that on his Hakkapelita 296 tyres. He would get a lot of snow on the tyres when the snow is wet, until it got to the point where the wheel would get jammed.

Anyway, my advice is: If you ride during the winter where it snows and you are likely to get below freezing temperatures, get studded tyres. It's safer and more comfortable than slipping and falling all over the place.

Magnus Thor
Iceland

Where in Alberta are you from?

Currently in Calgary. And watching the snow come down...studs will earn their keep tonight I'm thinking...but then again the ground might be cold enough that we don't get a layer of ice before the fluff builds up.

Prairie*boy

Would studded tires be of any benefit in wet leaves? Last October I had a slip and fall on my recumbent BikeE. Going downhill I hit a patch on a paved park trail, and ended up in the hospital with a broken femur. So much for "you don't have far to fall riding recumbent." I'm back on the bike, but I only have about 75% power in the bum leg. They say it will be a year before I'm back to full strength, just in time for the fall season. I've been fascinated by this thread, since I commute to work every day, and don't own a car. I have a mountain bike which is supposedly for days when it's just too yucky (snow, ice) to ride the recumbent, but mostly I just wus out and take the bus or bum a ride when conditions are horrible. I realize there are no studded tires for the small wheels on my recumbent. I'm thinking about putting them on the MTB and going for it next winter. Would they be any good with wet leaves? I live Mid Atlantic, I'm 59.

It's hard to say. I have used mine on the dirt, and they really grab well. The problem with the leaves is that even if you grab the leaves, they slide across the pavement.
I don't think it would make much difference. The studs have to dig into something that does not move to make a difference.