Hmmm...I had a good friend, IMG, who matched prelim into surgery. She worked her tail off but could never find/get a categorical surgery spot. She did end up getting an anesthesia spot later, but it took about 1.5 more years. Still, if you are dead set on surgery then taking a prelim spot would be an option...at most you waste a year or two, but in the long term scheme of things that is probably not too big a deal. I would advise that you rank all your categorical programs where you interview above ALL prelim spots, unless the categorical program seems like a complete rathole, because some of the prelim places like to promise the applicants ("Pretty much all our prelims continue to get a categorical spot, either here or somewhere else...") but if there's no contract, that doesn't mean crap. In other words, take the sure thing over any crapola someone feeds you at an interview.
