I do fine with the schwinn tubes from the grocery store. I carry two, about one time out of 50 the tube explodes right when I first inflate it. With the nearest supply 24 miles from my destination, it is a long walk if the last one I carry blows. I've had a premium tube from the bike shop do the same, so it is not worth riding 90 minutes over there to get those. If the bumps on my kenda tires are over 1/8" thick I don't get flats. They start out at 3/16" thick and last about 2000 miles. Major hazard here is shreds of truck tire with the wires sticking out, but there is also metal shards and broken glass on the pavement. No thorns. I don't use slime.