Good choice to choose NW for your ROC-TOL commute.

One other beneift of flying NWA through DTW that I forgot to mention. ALL of the NW AirLink (i.e. Saabs) and JetLink (i.e. CRJ and AVRO) planes are served by jetways at DTW.

At CVG, none of the gates in the Comair commuter terminal have jetways. One of my pet peaves is leaving dry Lansing, and arriving with soggy shoes at cold but dry Nashville, because the CVG ramp is wet. By flying through DTW, I never have that problem anymore. It makes for a more pleasant day.