I agree with you on that Primo Comet tire. After rideing in rough country like Oklahoma (goathead stickers) and especially New Orleans (broken glass) I have found the best thing is puting a "toughy" strip between the tire and the tube. A space to protect the tube is worth more than the Kevlar liners that are put in tires. If you really want to get serious use the strip, use high thread count tires and thick tubes. In the real world I had rather have a wheel that is a second slower per mile than have a flat 10 miles from home, in the middle of nowhere with the sun going down.