My Redline 29er needs an overhaul- the most critical parts I need to replace are the busted Shimano Nexus 8, and my worn-out rim brakes. I wasn't happy at all with Nexus hub or the rim brakes, so I am looking at the Sram I-Motion 9 hub and adding Sram I-Brakes (drum brakes) front and back. The technical manual says they are each rated for 125 kilos (275 lbs) for a total of 250 kilos (550 lbs). My bike, my gear, and I weigh in at 150 kilos combined. Think this is enough stopping power for mostly city biking? I don't want to get disc brakes because (A) they make my bike more of a target for theives, and (B) I lock my bike up to all sorts of objects many times a day, and I am worried about banging the rotors against something and damaging them. Anybody here with drum brake experience have any advice?