I use Tuffies. They are a tiny bit of extra weight but worth not stopping to repair a tire to me.
I finally got a flat after 6 years on the tuffy-it was caused by the liner wearing through the tube but remember, it took 6 years to do it. Tires usually dry-rot before then or the tread wears out.
Tuffies don't protect the sidewalls, only the tread, but for my road rides it was perfect. Nothing is more satisfying than digging a chunk of metal or glass out of a tire after a ride knowing you would have had a flat if your tire had not been protected.