Look at Welker, who almost never takes a direct hit. Look at Emmit Smith and Dunn, that followed blocking, and always ducked under the direct hit. Look at Walter Payton, that had such wonderful flexibility he could be bent backward and bounce right up. Reggie doesn't seem to have great flexibility, and has a special knack for getting hit right in the chest.
I'm as big a Reggie fan as anyone else, but if used as an every down back, he is an injury waiting to happen.