Here's something to consider; Disk brakes are not self energizing, and in anon-boosted system, can take excessive pedal pressure to get them to effectively stop a vehicle. The Bendix style drum brakes, properly called Duo-Servo, are self energizing. This self energizing action will allow a non assisted drum system be more effective than a non assisted disk brake system. With an assisted system, drums can get very touchy, particularly if they're not properly adjusted. Disk brakes are much more predictable in an assisted application.
I can see disk brakes if you plan on oversized wheels/tires, or possibly if you do lots of driving on twisty or mountain roads. But for normal driving, non assist drums work just fine, even running highway speeds.
