All three bikes have Mr. Tuffys. On the26x1.75 MTB based commuter I didn't have many flats. When I acquired an old 700x23 roadbike I had flats every coupla weeks. Mostly goathead thorns. Tire liners solved this. Later switched to 700x32s and kept the tire liners. Put them in the MTB commuter for good measure and no more flats except a 4-inch roof nail through the sidewall. On the "new" bike, also 700x32 I went 6 months without tire liners and had a flat every 2-three weeks. Finally put in liners. No flats except that sheet screw last month. I have had no tube problems from the tire liners.