Here's what you need to consider before buying ;
Always consider your driving style and local conditions. If you don't see much snow during the winter, and you like to drive/corner fast on cold dry roads then look into the H-rated or V-rated "high performance" winter tires like the Bridgestone Blizzak LM60 or Dunlop Winter Sport 3D.
If your area gets heavier snow, and/or are often driving on packed snow and ice then look into a more aggressive "Studless Ice and Snow" tire. Among the best of this type are the Blizzak WS-70, Michelin XIce XI3, and Continental Extreme Winter Contact. Winter tires like these will offer the best in snow and ice traction, but will give up some dry road responsiveness over the more performance oriented H/V rated snow tires to get that additional traction.
If deep snow is your only concern and ice is almost never an issue, you can save some money and get the Firestone Winterforce or General Altimax Arctic. These two models have very aggressive tread patterns that make them exceptional in snow, but they lack the specialized rubber compound needed for good ice traction (which makes them less expensive). You can add studs to either model ( $15) to improve traction, but studs have been outlawed in many states and may put the combined price of the tire and studding very close to a Studless Ice and Snow tire......
Choosing between these two categories may be difficult and is mostly a personal preference choice for the trade off between snow traction versus dry road handling. Any dedicated snow tire will do better than a standard "all season" tire in light snow and ice, but keep in mind the worst conditions the tire may see and use that as a frame of reference.
--New/Updated products for 2012/2013 season:
The Michelin XIce XI3 has replaced the XI2 in nearly all sizes (with remaining sizes marked down for clearance). The tread pattern appears to be very similar between the two, but Michelin has increased the speed rating on the new model (in most sizes) in an effort to improve the "clear road" handling compared to the previous model. The Michelin Pilot Alpin PA4 will be slowly replacing the Pilot Alpin PA3 in a few sizes this season as well, with the same goal of improving dry road handling.
A few years back, the Bridgestone Blizzak LM60 replaced the Blizzak LM25. In the past the Blizzak LM25 and the popular Dunlop WinterSport 3D tires were considered very equal to each other in snow traction and in dry road handling/cornering and were the tires of choice in this category. The redesigned LM60 is moves the balance closer to the snow traction side of the equation by using the more aggressive tread pattern of the WS60 but with a compound and construction of a high performance snow tire like the Dunlop WinterSport 3D. This tire will be an ideal choice for someone having trouble deciding between the high performance snow tires that sacrifice a lot of snow traction and the Studless Ice and Snow tires that lack crisp handling and dry grip. Having used the LM60 on my Pontiac G8 GT last year, I feel the LM60 ideally suits many drivers needs in this forum well for an ideal balance of snow/ice traction while still keeping acceptable dry handling and grip for the non-snowy days.
And one last thing;
Don't wait too long. Ordering early when most products are still available lets you choose what you want to buy rather than being forced to settle for what is left over. We have been hit with delays and shortages from our manufacturers already ! Tires and wheels purchased together are mounted and balanced at no charge to make changeover easy, and Genuine GM TPM sensors can be added for $ 35 per wheel.
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