Also, if flats are a huge concern, then like we all have been saying, get the highest flat resistant tire on the market which is the Schwalbe Marathon Plus, you will pay a weight penalty starting at around 480 grams which isn't awful, but the Marathon Plus Tour is a 1,000 grams, sort of crazy heavy, but you won't have to ever fix a flat...well, ever might be stretch! If you are still concerned about flats than run a pair of Clear Motion Rhinodillos tire liners for absolute insurance against flats. The Rhinodillo is far better than a Mr Tuffy, it's more difficult to cut, and I couldn't get a tack to penetrate it but it did penetrate a Mr Tuffy fairly easily. The only way you would get a flat from using the Marathon Plus, or Plus MTB, or the Plus Tour (a very long distant tire), and a Rhinodillo is if you hit something that destroyed the tire like a curb or a large rock, etc, but glass, bits of wire, thorns, the everyday normal stuff found on streets won't flat that combo. I have a pair of Schwalbe Almotion tires with Rhinodillos and I roll over fields of glass all the time on the side of highways and never had a flat, and those tires aren't as tough as the Marathon Plus!