They are very little different. The tires are much more important and real snow tires are far better than all season tires.
Like with any product, depends on the tire and manufacturer. They are much better than normal tires in icy conditions.
From what I know, they probably do not because snow tires have special pins build into it for gripping the snow/ice. It depends on the type of tire you are actually going to buy but generally mud tires are more expensive than snow tires.
Yes. They are not as good as dedicated snow tires-- which are designed with compounds that grip better in low temperature conditions. But, they do grip better in snowy conditions than normal tires.
Snow tires cost slightly more than all weather tires. The actual cost of the snow tires would depend on the brand, style and size.
No wide tyres or better because the give more grip Actually wider tires don't give you more grip in snow. They simply allow more snow to pile up in front of the tire. On Ice or snow pack a wider tire will provide better grip but in deep snow the thinner tire works better. Chicago winters taught me that.
Winter tires and snow tires are often used interchangeably, but technically winter tires are designed to perform well in a variety of cold weather conditions, including snow, ice, and cold, dry roads. Snow tires, on the other hand, are specifically designed to provide enhanced traction in snowy and icy conditions. Snow tires typically have a more aggressive tread pattern compared to winter tires.
No, snow tires aren't necessary for a vehicle with 4-wheel drive. You should look at the type of terrain your vehicle will be driven on most frequency. If you live in a place where there is more snow-fall than sunshine, snow tires might be a good fit. If you live somewhere with all 4 seasons, all-weather tires might be a better fit.
Why do you assume there is ice underneath the snow? In most instances there is no ice under the snow. The narrow tire can get down to the pavement easier than a wide tire.
If you live in an area where you will regularly drive in snow you should buy snow tires. While all-season tires are designed to cope in all kinds of weather conditions they are not designed to optimally deal with all conditions. In particular, they perform less well in cold conditions which would include snow and ice. The tread on snow tires is designed to grip the snow and ice better than any other tire.
They are entry level tires and rank pretty low in the mix of things. They are average snow tires but any winter tire is better than not having anything at all.
If the snow tires have a bigger diameter than the others, the odo and the speedo will read a bit low. If the snow tires have a smaller diameter the odo and speedo will read a bit high.