Just a little update on the result of this effort to avoid or minimize punctured tubes. I made it 346 miles without a puncture using the tire liners. They definitely added to rolling resistance, but on Tuesday (08/08) I was almost home from a 25-mile trek and had a flat on the front. I stopped to install a spare tube and thoroughly inspected the inside of the tire. It appeared that whatever had caused the flat was now gone. I aired the tire up using CO cartridge and continued on home. Last night I got a chance to tear things down and do a more complete inspection in the comfort of my shop. I still could not find anything in the front tire but did notice the Slime liner was off center for about 6" on either side of the valve. I decided to take a closer look at the area around the leak in the tube. There was a definite line where the liner had dug its way into the tube and the leak was dead in the middle of that line. I inspected the tube further and discovered the line caused by the edges of the liner were all the way around the tube. I suspect that the portion of the edge of the liner that had worked its way around to being under the tube instead of on the side caused that part to form the leak. I then began to fold the tube along the line and noticed that gave it the appearance of being cracked all along that line; even where the liner had stayed in place and the line was well up on the sides of the tube. This has caused me to rethink the use of the liners. I removed both of them last night and will be making a ride early in the morning for a "seat of the pants" comparison of the rolling resistance as well as keeping up with frequency of flats per mile just as in the past. My next purchase at the LBS will likely include pre-slimed presta valve tubes.