If I did most of my driving on flat pavement, I would definitely use the siped tires, exclusively. However, driving steep, winding mountain roads that have 5 Months of ice in patches at a minimum and snowpacked hills that are 3+ miles long at a 15% Grade in one place with no guard rails, I'll stick with what works, Studs! I have had no issue with driving with studs at highway speeds. The proper stud for the tire was used. My tires are worn out when the studs are gone. I have never gotten more than 30,000 miles from any tire! With 2 sets of rims, running allweather tires in the Summer and studded M&S in the Winter, I get about 4 years worth of use. However, the service time will lengthen, cause I dont drive that much with the high fuel costs. GregH