Depends. can't generalize like that. Take for example a 12"x3 front drum vs. 10" dia disk with a small pad and everything else is equal. In some ways its never equal because some people judge by braking effort on their foot. A duo-serve drum setup kicks butt in that regard. You can go on and on. Its all about how it works as system and whatr your goals are. For road racing and such, a well done disk setup is almost always preferable...