Has anyone done this?

I'm considering either a Cannondale Optimo Disc, Trek Portland, Salsa La Cruz or Poprad Disc. The Poprad Disc doesn't have eyelets to mount a rack, and an LBS which wants to sell me a Portland claims that it's difficult to get a disc-compatible rack w/ p-clamps to be stable.

Please keep replies to the "rack" issue- I already know that there are people who don't like disc brakes. To each his own.