I'd say both were dominant and even similar in style. Sharpe had his career cut short, so D would get the nod from that standpoint. As for "at their best" I'm not sure I can pick a winner.

I just took a quick peak. Sharpe actually didn't miss a game through 7 years by the looks of it. D missed plenty. Through 7 years its super close, but D kept playing and had back to back 1500 yard seasons for career highs.

Prior to Adams playing longer than Sharpe I would easily have went Sharpe. Those last 2 years have been special, and for a post 30 y.o. WR, he is still balling big time.