Most running shoes have a run shelf between 400-500 miles at the highest limit. Saucony is a great ride, they can be very cushiony depending on which you got. If you also wear the shoes daily that'll significantly wear on the shelf life. If you plan on getting another pair bring in your old pair. A good sales person would be able to tell if the shoe you were fitted for is working great or you may need a change, by the wear pattern.