@mmgreve: I haven't flown any canard either, but I learned canard pilots prefer "clean" runways (normally translating to "hard" runways) because any debris thrown up by the wheels risks damaging the pusher prop normally associated with the canard design.
Also, canards seem to have higher-than-usual stall- and approach speeds (though I wouldn't know why), requiring longer runways indeed.
@IO540: if canards made a spectacular improvement, they'd be all over the place - just like diesels. Pilots are a remarkably conservative bunch, private pilots not the least: they'll only change their preferences if and when they really have to.