I have Conti Ultra Sports and they're real soft; I've only had 'em for two months and they're pocked full of little holes where I did or didn't get flats. Next time I'm planning on Armadillos, Gatorskins, or Marathons, to be decided later. IMO, slick tires without flat protection don't belong in city streets. Currently running 28's but thinking about 25's. Trying to get an answer about whether the thinner ones or the thicker ones will be faster is about as polarizing as asking "should I get an abortion or not?"