Almost all of the young guns have a good serve but witch of Gasquet, Djokovic, Berdych, Murray, Monfils and Baghdatis have the best First and Second serve. And if you where a tennis player witch serve would you want to have among these?
Murray for the pace, variety and precision. Although he has yet to have his serves in relatively high percentages on a consistent basis, the quality is there. The rest -- Djokovic, Berdych and Gasquet, in that order.