Although a two-disc clutch will get the job done, a three-disc clutch will operate at a much lower temperature. The wear rate of friction materials varies exponentially with temperature i.e. a three-disc clutch has about 50 percent more heat capacity than the two-disc clutch but possibly 100 percent more longevity. Consider too that the three-disc clutch costs only 8 percent more.
The added weight affects acceleration by less than .0003 second.