I have a flat on the rear tire of my XC. The tire is a steel belted E-4. I am going to plug it with the Stop and Go mushroom plug kit. Reading the directions on the plug kit. It states that on steel belted tire you should replace the tire after plugging as soon as possible. What's your feelings? run it or replace it. The tire has maybe 3,500 miles on it. I have ran plugs in steel belted truck tires for years with no problems other than they sometimes start leaking and that is using rope type plugs.