I've got an 02 SX600/R bone stock and just turned 3500 miles today.My buddy asked me if I had replaced the carbides and when I told him no he was suprised. I had been planning on changing them next fall unless I noticed the sled pushing in corners at some point this winter then I would change them right away. The sled has been corning like it is on rails this winter even through the ice so I figured it was fine. Today as we were loading my sled into my truck my buddy looked at the bottom of my skis and noticed that the skags were worn down almost to the ski. I was amazed as I have been riding aggresively all day for the last three days and have been hugging the right side banks the whole time with no problem. I'm just amazed that the sled is still so stable with such a worn scag and I'm wondering how much of a diffrence I'm going to notice when I put a new set of carbides on.