It depends. I'm paraphrasing Susan at TE here, but as she explained it, saddle life depends on a handful of factors--how much foam it has, how fast/hard you ride, what kind of weather conditions you ride in, whether the saddle has a cutout. As a point of reference, my Terry Butterfly Tri Gel started to become less comfortable after about a year/4,000 miles. I'm about due for another saddle, but I'm waiting for actual discomfort to set in. Susan indicated that that was pretty standard for that particular saddle given the way generally I ride.