Tufo makes some 28mm wide cyclocross tubulars with a very mild chain tread. I beleive they're available in 65 and 90 psi versions. I have a pair of the 65 psi tires on my BSA fixed-gear. They feel really nice and don't buzz on pavement. They went on easily and are round and have no wiggles or bumps. Air stays in them for a long time. The bad thing is the color: bright red tread with bright yellow sidewalls. I don't think they can be repaired in the normal fashion, but Tufo sells goop to spary inside to seal the hole. I haven't flatted yet, so I don't know how well it works. Price was something like $65 each.
Leonard Bulger
Ann Arbor, MI